DE102021101996A1 - Process for post-processing of additively manufactured components by blasting with plastic blasting media - Google Patents

Abstract

The invention relates to a method for treating a component with blasting agents and a shaped body produced by the method according to the invention. Furthermore, the invention relates to a blasting system and the use of the blasting system according to the invention for the method according to the invention.

Description

The invention relates to a method for treating a component with blasting agents and a shaped body produced by the method according to the invention. Furthermore, the invention relates to a blasting system and the use of the blasting system according to the invention for the method according to the invention.

Blasting as a treatment method with blasting agents is known from numerous industrial applications. The known blasting processes can be classified according to the blasting agent used.

For example, blasting with conventional blasting media such as quartz sand (sandblasting) in particular, but also with other conventional blasting media such as steel grit, chilled cast iron grit, wire shot and corundum. These conventional blasting agents have the common property that the blasting agents are in a solid aggregate state under normal conditions. They usually have an abrasive effect. Blast treatment using conventional, abrasive blasting media is usually accompanied by a large amount of dust (from the blasting media and the blasted material). This strong formation of dust is mostly undesirable. In addition, high costs arise due to the necessary disposal of the blasting agent contaminated with blasted material.

Blasting systems are used to treat the surfaces of components. In this case, blasting material (sometimes also referred to as blasting medium) is blasted into a process chamber of the blasting system using a blasting nozzle, with the process components to be treated being located in the process chamber. The surface of the components is treated by the physical interaction of the particles of the blasting material with the surface of the components. For example, dirt or contaminants can be removed from the surface, porosity reduced, etc.

Components that have been manufactured in a powder bed using an additive process such as laser melting, for example, must be freed from the unfused particles of the powder bed after the manufacturing process. This process is referred to as de-powdering in the field of additive manufacturing. A common method for depowdering additively manufactured components is to blast the components with abrasive particles that are accelerated by a medium such as air or water and remove the unfused powder particles from the component by hitting them.

If the additively manufactured component has been gently freed from the powder, the rough, open-pored surface of the component comes to light. Depending on the application, there may be a need for further surface treatment. The original, untreated surface is not always desirable. One possibility for further treatment of the surface is compaction blasting, also known as "shotpeening". During this process, the initially open-pored surface of the additively manufactured component is compacted. The pores can be closed to a certain extent, the surface becomes smooth and shiny. In addition, the surface becomes more homogeneous. In order to achieve this effect, the components are also irradiated by particles that are accelerated by a medium such as air or water. The difference to the depowdering process described above is the selection of the particles that are accelerated. On the one hand, these should not be too abrasive, on the other hand, the particle shape should be appropriate in order to achieve the compaction effect.

The challenge in the depowdering process is not to damage the component or its surface, not to change the surface of the component in any way, or to remove particles that have already melted. The component must be processed so gently that subsequent processes, such as the compression process, are not impaired.

Furthermore, ceramic beads or plastic beads are predominantly used in the prior art in the compression process. These are also used in pressure or injector blasting systems, in which the particles are accelerated using a medium such as air or water.

For example, describes the EP 3 444 073 a surface treatment method in which the same abrasive is used in the first and second steps. The blasting media described in the document are, for example, ceramics, glasses or metals.

the EP 1 034 890 A2 describes a device for blasting with different types of blasting agents. The blasting agents that are described there are, on the one hand, dry ice for the first blasting agent and, as the second blasting agent, a conventional abrasive blasting agent. The known abrasive conventional blasting agents can lead to an unwanted modification of the surface of the component to be manufactured.

Glass beads, ie glass particles with a spherical or drop-shaped grain shape, are therefore used as the preferred blasting medium in the depowdering process in the prior art. These are used in pressure or injector blasting systems, in which the glass particles are accelerated using a medium such as air or water.

Here, a blasting pressure of 1.5-6 bar is typically used, preferably 2-3 bar. The process time, i.e. the duration of the blasting process, can be between 1-90 minutes, depending on the quantity and geometry of the components to be processed. preferably 5-10 minutes.

Depending on the grain size and blasting pressure, the high mass of the glass particles usually used can lead to damage on the component surface of additively manufactured components. This means that the glass particles are sometimes accelerated so much in the blasting process that particles that have already melted are removed from the surface, or fine geometries on the surface of the component break off/are damaged.

The blasting agents normally used for depowdering, such as "glass beads", i.e. round or bead-shaped glass blasting agents, often have the undesirable side effect that the beads have a surface-changing effect when they hit the surface of the component due to their shape and mass - the surface is compressed. This effect is undesirable because the component should be freed from the residual powder without changing the surface if possible. In addition, the densification of the surface causes light to be reflected, making the surface of the components shiny. The surface-changing effect should only take place in the subsequent compaction process, if desired.

In principle, with commonly used blasting abrasives on a metal or mineral basis, such as glass beads, broken glass or metal balls, during the depowdering process, due to acceleration and mechanical stress on the blasting abrasive particles in the blasting process, blasting abrasive breakage or abrasion occurs, which can be found on or in the surface of the additively manufactured plastic components sets. As a result, the surface is contaminated and damaged, and the material purity of the components is impaired. This is particularly a problem in combination with subsequent surface treatment blasting processes, such as blasting the surface using round or bead-shaped blasting media to compact the surface. This means that the broken blasting agent or abrasion that settles on or in the surface of the components during the depowdering process is shot even deeper into the surface due to the kinetic energy of the subsequently used compaction blasting beads and/or the dirt lying on the surface into even smaller ones Components atomized.

Impurities, changes and damage to the surface also mean that subsequent processing steps, such as surface treatment processes, coloring processes or coating processes, are impaired.

Contamination must be prevented, as this contamination leads to problems in further processing steps, such as coloring, infiltration or coating processes, because the chemicals designed for coloring, infiltration or coating of the additively manufactured components do not adhere to the unwanted particles on the surface. Dyes, for example, are not able to color the unwanted particles on the surface. The application of paint or ink penetration is thus impeded, and the homogeneity and processing quality of the components is impaired. Furthermore, the compaction of the surface during the depowdering process must be avoided, since the ink penetration can be impaired.

In addition, the uncontrolled breaking of the blasting media normally used means that the cleanliness of the blasting media in the machine circuit is impaired. Due to the fact that the fracture or abrasion during the process occurs in different grain sizes, material separators, such as inertial separators or screening devices, can no longer be optimally designed. So there are always unwanted particles in the blasting agent that is returned to the machine cycle.

Due to the different grain sizes that are used in the process of common blasting abrasives, there is also an increased post-processing effort. The additively manufactured components have a wide variety of geometries in which blasting agent particles can get stuck. These then have to be removed manually after the blasting process. The greater the grain size variation in the abrasive, the greater the likelihood that particles will get stuck in different geometries.

Another problem is the abrasiveness and aggressiveness of the blasting agents normally used. During the conveyance of the blasting media through the blasting machines used, the machine components are increasingly damaged.

In addition, there is another problem that results from the problems described above: In order to design the two processing steps, i.e. the depowdering process and the compression process, to be of high quality, the processes usually have to be carried out on different systems. So there are usually two machines, each equipped with a blasting medium for depowdering or compaction.

As already described, in the prior art, glass beads are used in the depowdering process and ceramic beads are used in the densification process.

There is therefore a need for an improved method for treating a component with blasting agents. In particular, there is also a need for blasting systems that combine the processes in one system in order to enable an efficient and gentle process for the surface treatment of a component.

This object is solved by the features of the independent claims. The features of the dependent claims define particular embodiments.

1. a) Bereitstellen eines Bauteils in mindestens einer Strahlanlage, wobei das Bauteil vorzugsweise mittels additiver Fertigung erstellt wurde,
2. b) Behandlung des Bauteils mit mindestens einem ersten Strahlmittel, wobei das erste Strahlmittel ein Kunststoffstrahlmittel A umfasst,
3. c) Behandlung des Bauteils mit mindestens einem zweiten Strahlmittel, wobei sich das zweite Strahlmittel vom ersten Strahlmittel unterscheidet.

The invention therefore relates to a method for treating a component with blasting agents, comprising the steps:

1. a) providing a component in at least one blasting system, the component preferably being created by means of additive manufacturing,
2. b) treatment of the component with at least one first blasting agent, the first blasting agent comprising a plastic blasting agent A,
3. c) Treatment of the component with at least one second blasting agent, the second blasting agent being different from the first blasting agent.

The invention also relates to a shaped body produced by the process according to the invention.

• - ein Gehäuse,
• - eine Prozesskammer, die im Gehäuse ausgebildet ist,
• - eine Strahldüse oder mehrere Strahldüsen oder ein Schleuderrad oder mehrere Schleuderrräder, die in der Prozesskammer ausgebildet sind, wobei die eine Strahldüse oder die mehreren Strahldüsen oder das eine Schleuderrad oder die mehreren Schleuderrräder in Verbindung mit mindestens zwei Strahlgutbehältern, enthaltend
  1. a) ein erstes Strahlmittel, wobei das erste Strahlmittel ein Kunststoffstrahlmittel A umfasst, und
  2. b) ein zweites Strahlmittel, wobei sich das zweite Strahlmittel vom ersten Strahlmittel unterscheidet, steht/stehen.

Another subject of the invention is a blasting system, comprising:

• - a housing,
• - a process chamber formed in the housing,
• - a blast nozzle or several blast nozzles or a blast wheel or several blast wheels, which are formed in the process chamber, wherein the one blast nozzle or several blast nozzles or the one blast wheel or several blast wheels in connection with at least two blasting material containers, containing
  1. a) a first blasting agent, wherein the first blasting agent comprises a plastic blasting agent A, and
  2. b) a second blasting medium, the second blasting medium being different from the first blasting medium, is/are standing.

A blasting system within the meaning of the invention is a system for treating the surfaces of components. In this case, the blasting system comprises a housing, for example, it being possible for a process chamber to be formed in the housing. The process chamber can optionally be loaded from the front, for example. For example, a door could be attached to a front side of the process chamber, optionally a lifting door, which can be moved up or to the side, for example.

A component within the meaning of the present invention can be a metallic component, a ceramic component, a quartz component, a plastic part or a composite material. For example, plastic parts could an injection molding process. It would also be conceivable to use the method according to the invention to treat components, in particular plastic components, which were produced by a 3D printing process, for example a powder bed process.

The components, which are produced in a powder-based manufacturing or printing process, can be made from a material selected but not limited to the group comprising polyamide, in particular polyamide-11 and polyamide-12, thermoplastic polyurethane, aluminum-filled polyamide, in particular aluminum-filled Polyamide-12, glass-filled polyamide, carbon-reinforced polyamide, sand, gypsum, metal, composite material, thermoplastics, thermoplastic elastomers, polyolefins, polystyrenes, polyesters, polyimides and thermoplastic elastomers and combinations, blends or copolymers and filled variants (e.g. with glass, carbon fibre, aluminum) thereof.

An example of a powder bed process would be a selective laser sintering (SLS) process, in which the body of the plastic component is built up step by step. Other examples of powder bed processes include MJF, high speed sintering and binder jetting.

A (plastic) blasting agent within the meaning of the present invention can comprise an agent comprising at least one type of particle during the blasting process, which is also accelerated onto the object to be treated with the aid of a medium, in particular a gas. In particular, a plastic blasting agent can be constructed at least partially from a plastic.

1. I. eine Injektor-Düse oder Venturi-Düse, also eine Düse die nach dem Injektor Prinzip funktioniert, bestehend aus:
   1. a. mindestens einem Gehäuse,
   2. b. mindestens einem Gas (vorzugsweise Druckluft) Anschluss für Gas Schläuche oder Rohre,
   3. c. mindestens einem Strahlmittel Anschluss für Strahlmittel Schläuche oder Rohre,
   4. d. mindestens einer Luftdüse, durch die die das Gas (vorzugsweise Druckluft) in das Strahldüsengehäuse gefördert wird,
   5. e. mindestens einem Strahlkern, durch den das Gas / Strahlmittel Gemisch aus der Strahldüse gefördert wird.

A jet nozzle within the meaning of the present invention

1. I. an injector nozzle or Venturi nozzle, i.e. a nozzle that works according to the injector principle, consisting of:
   1. a. at least one housing,
   2. b. at least one gas (preferably compressed air) connection for gas hoses or pipes,
   3. c. at least one blasting agent connection for blasting agent hoses or pipes,
   4. i.e. at least one air nozzle through which the gas (preferably compressed air) is conveyed into the jet nozzle housing,
   5. e. at least one blasting core through which the gas / blasting medium mixture is conveyed out of the blasting nozzle.

• II. eine Druckstrahldüse, also eine Düse für den Einsatz in Strahlanlagen nach dem Druckstrahlprinzip, bestehend aus:
  • f. mindestens einem Gehäuse,
  • g. mindestens ein Anschluss für ein Gas/Strahlmittelgemisch,
  • h. vorzugsweise einer Einlassdüse, die die Eintrittsgeschwindigkeit und das Strömungsverhalten des eingeleiteten Gas-Strahlmittelgemisches beeinflusst,
  • i. vorzugsweise einem Strahlkern, durch den das Gas / Strahlmittel Gemisch aus der Strahldüse gefördert wird,
  • j. optional einem zusätzlichen Anschluss, durch den gemäß des Venturi-Prinzips ein zusätzliches Medium (Beispielsweise Wasser, z.B. beim Feuchtstrahlen) dem Gas-Strahlmittel Strom hinzugeführt werden kann.

Due to the geometric design of the interior (housing) of the nozzle and the correspondingly coordinated diameter of the air nozzle and blasting agent connection, a so-called Venturi effect is created when a gas (preferably compressed air) is conveyed through the blasting nozzle. The Venturi effect creates a negative pressure at the connection of the blasting agent hose (or pipe). The blasting agent is sucked in by the negative pressure, conveyed into the interior of the nozzle, entrained by the gas flow and accelerated/conveyed out of the nozzle through the blasting core or

• II. a pressure blasting nozzle, i.e. a nozzle for use in blasting systems based on the pressure blasting principle, consisting of:
  • f. at least one housing,
  • G. at least one connection for a gas/abrasive mixture,
  • H. preferably an inlet nozzle that influences the inlet speed and the flow behavior of the introduced gas-blasting medium mixture,
  • i. preferably a blasting core through which the gas / blasting agent mixture is conveyed out of the blasting nozzle,
  • j. optionally an additional connection through which an additional medium (e.g. water, e.g. with wet blasting) can be added to the gas blasting medium according to the Venturi principle.

Here, a blasting media container is pressurized (preferably compressed air). The pressure in the blasting agent container is periodically relieved via the blasting nozzle, so that the gas-blasting agent mixture that is produced in the blasting agent container is pressed into the blasting nozzle, accelerated if necessary and then accelerated/conveyed through the blasting core out of the blasting nozzle. Optionally, the beam The nozzle in the interior should be designed similarly to the injector jet nozzle described above, so that a Venturi effect occurs in the interior due to the flow of gas and abrasive. The Venturi effect creates a vacuum at an optional, additional connection. Due to the negative pressure, an additional medium can be supplied to the gas blasting medium flow.

1. a) von außen dem Schleuderrad hinzugefügt werden, sodass der Strahlmittelstrom von diesem bzw. von dessen Schaufeln mitgerissen und in die gewünschte Richtung beschleunigt wird
2. b) von innen dem Schleuderrad hinzugefügt werden, sodass das Strahlmittel durch die Rotation des Schleuderrads Zentrifugalkraft erfährt und somit vom Innenraum des Schleuderrads über Öffnungen nach außen getrieben wird, und über das Schleuderrad beziehungsweise dessen Schaufeln in die gewünschte Richtung beschleunigt wird.

A centrifugal wheel within the meaning of the present invention is a wheel or bucket wheel or centrifugal wheel which is set in rotation and which is accelerated to a desired speed. As the wheel rotates, the abrasive is fed to the wheel. The blasting agent is carried along by the rotation of the wheel or its blades and accelerated in the desired direction. Here, the blasting agent

1. a) be added to the blast wheel from the outside so that the blasting medium flow is entrained by it or by its blades and accelerated in the desired direction
2. b) be added to the blast wheel from the inside, so that the blasting agent experiences centrifugal force as a result of the rotation of the blast wheel and is thus driven outwards from the interior of the blast wheel via openings, and is accelerated in the desired direction via the blast wheel or its blades.

The invention is preferably a combination of two blasting steps, the depowdering process (first step, which includes treatment with a first blasting agent) and the compaction process (second step, which includes treatment with a second blasting agent), with the depowdering process preferably an angular, therefore for example a cylindrical or cubic, plastic blasting medium is used. In the subsequent compression process, a plastic blasting agent in a spherical shape is preferably used. Preferably, a spherical shape can be a structure that does not include edges.

In the method according to the invention, the plastic blasting agent A preferably comprises at least one particle PA1 made from at least one polymer KA1 and at least one foreign particle FA1. In the method according to the invention, the plastic blasting agent A very particularly preferably consists of at least one particle PA1 of at least one polymer KA1 and at least one foreign particle FA1, with additives and/or adhesion promoters preferably also being present.

The first blasting agent in the method according to the invention also preferably includes a plastic blasting agent B, with the plastic blasting agent B comprising at least one particle PB1 made from at least one polymer KB1 and at least one foreign particle FB1. The plastic blasting agent B very particularly preferably consists of at least one particle PB1 of at least one polymer KB1 and at least one foreign particle FB1, with additives and/or adhesion promoters preferably also being present.

An additive leads, for example, to improved properties with regard to static charging, tensile strength, impact strength or elongation at break. An additive may include thermal stabilizers, weatherability components, stabilizers, fillers, or other components known to those skilled in the art.

In contrast to mineral substances or metallic substances, a corresponding plastic blasting agent A and/or B has a lower abrasiveness, lower mass and lower hardness, so that the flexibility of the plastic blasting agent during interaction with the materials of the machine components does not cause damage of the component of a blasting system or components of a blasting system.

Due to the fact that the plastic blasting media A and/or B used is flexible and has a hardness similar to that of the blasted components, as well as its low mass and thus lower kinetic energy in the depowdering process, damage to the surface is advantageously avoided.

One way of specifying the hardness of plastics is to determine the shore hardness. For example, if the Shore hardness of the component to be treated is known, the Shore hardness of the blasting agent can be adjusted accordingly.

The polymer KA1 and/or KB1 in the process according to the invention therefore preferably has a Shore hardness of 10 Shore A to 95 Shore D, particularly preferably 35 Shore A to 93 Shore D and very particularly preferably 70 Shore D to 93 Shore D.

The second blasting agent can also be configured flexibly. The second blasting agent therefore preferably comprises a plastic blasting agent S, with the material of the plastic blasting agent S being selected from the group consisting of polyamides, resins, polyesters, polystyrenes, polyolefins, polyvinyls, rubbers, polyphenylenes, polyethers, polyurethanes, polysaccharides, polyimides, polyacrylates, Silicones and blends and copolymers thereof.

Advantageously, the plastic blasting agent S can be made up of polystyrene, which is preferably used after the polymerization process of styrene. By using this plastic blasting medium S, the surface of the component can preferably be compacted in a particularly gentle manner, so that, for example, a subsequent coloring step leads to a uniform coloring.

Preferably, the second blasting agent in the method according to the invention comprises a plastic blasting agent S, which comprises at least one particle PS1 made of at least one polymer KS1 and at least one foreign particle FS1, with an additive or adhesion promoter preferably also being present. The plastic blasting medium S particularly preferably consists of at least one particle PS1 made of at least one polymer KS1 and at least one foreign particle FS1, with an additive or adhesion promoter preferably being able to be additionally contained

As with the aforementioned plastic blasting agents A and/or B, the use of a plastic blasting agent S results in less interaction with the materials of the machine components and less damage to the surface of the component.

In the method according to the invention, the foreign particles FA1 and FB1 are preferably selected from the group consisting of metals, minerals, soot particles, salts, carbon fibers, color particles, ceramics, polymers, alloys or glasses.

In the method according to the invention, the foreign particle FS1 is preferably selected from the group consisting of metals, minerals, soot particles, carbon fibers, color particles, ceramics, polymers, alloys or glasses.

1. 1. Compoundierung (beispielsweise wird ein Kunststoffgranulat mit (Glas) gemischt), oder
2. 2. Extrudierung (beispielsweise wird die Mischung in einem Extruder erhitzt, Kunststoff wird durch eine (500µm) Düse extrudiert, ein Kunststoffstrang entsteht), oder
3. 3. Verstreckung (beispielsweise wird der Kunststoffstrang versteckt, also in die Länge gezogen. Ein (400 µm) Kunststoffstrang entsteht), oder
4. 4. Granulierung (beispielsweise wird der Kunststoffstrang in (400 µm × 400 µm) große Partikel geschnitten), oder
5. 5. Siebung (beispielsweise wird das Granulat ausgesiebt, um fehlerhafte Korngrößen zu entfernen).

The plastic blasting agent A, B or the plastic blasting agent S is preferably produced in the method according to the invention by a compounding process, an injection molding process, precipitation polymerization or an extrusion process. The plastic blasting agent A and/or B is preferably obtained by:

1. 1. Compounding (e.g. a plastic granulate is mixed with (glass)), or
2. 2. Extrusion (e.g. the mixture is heated in an extruder, plastic is extruded through a (500 µm) nozzle, a plastic strand is formed), or
3. 3. Stretching (for example, the plastic strand is hidden, i.e. stretched. A (400 µm) plastic strand is created), or
4. 4. Granulation (for example, the plastic strand is cut into (400 μm × 400 μm) large particles), or
5. 5. Screening (e.g. the granules are screened out to remove incorrect grain sizes).

The plastic blasting agent A and/or B is preferably obtained by carrying out steps 1 to 5.

The particles PA1 and/or particles PB1 used in the method according to the invention is or are preferably obtained from a strand granulation, a belt granulation, a dry granulation, an underwater granulation, a cutting granulation or a milling process. Due to the processes, the particle PA1 and/or PB1 can be cylinder granules, cube granules, lens granules, chip granules or polygonal granules. A polygonal granulate can be obtained from a milling process. This type of processing allows the particles PA1 or particles PB1 to have a polyhedral shape.

The foreign particles FA1 and FB1 are preferably admixed in the compounding process, the injection molding process or the extrusion process.

Therefore, preferably the particle PA1 and/or the particle PB1 in the method according to the invention has a polyhedral shape, for example a convex polyhedron, or a cylindrical shape. In the context of the present invention, the shape of a polyhedron can also contain dents, i.e. the connecting line from two points of the polyhedron does not necessarily lie in the polyhedron. Another term for a polyhedral or cylindrical shape can also be the term "angular" shape.

In a preferred embodiment, a polyhedral shape includes a cubic or prismatic shape.

In the method according to the invention, the particle PA1 and/or the particle PB1 preferably has a cubic, prismatic, polyhedral or cylindrical shape.

By using the angular (e.g. cylindrical, polyhedral, cubic or prismatic) plastic blasting media in the depowdering process, which preferably has a similar hardness as the additively manufactured plastic components, the risk of damaging the surface is reduced to a minimum. There is more flexibility in the selection of the grain size, and if desired, you can work with a higher blasting pressure. In addition, significantly finer structures or geometries can be processed.

The compaction of the surface is also advantageously completely avoided by using a blasting agent with an angular particle shape in the depowdering process. One is more flexible in the selection of the grain size, one can work with higher blasting pressure if desired, since the mass of the plastic particles is significantly lower compared to mineral blasting media.

Due to the higher breaking strength of the particles and the fact that the plastic has a hardness similar to that of the additively manufactured components, there is advantageously no significant damage when the particles are transported through the blasting systems or when the particles impact the surface of the additively manufactured components Abrasion or breakage and therefore no contamination on the surface. This means that you are much more flexible in the selection of the blasting pressure and the process time. In addition, complex material separators can be dispensed with. The blasting agent can also be used in the circuit for a significantly longer period of time without having to be replaced.

For material separators, the grain size and the mass of the particles that are to be separated are particularly important. Even if abrasion should occur, this differs in particle size/mass so much that the material separators are not affected.

Subsequent processing steps are not impaired by these described properties of the blasting agent used, in particular the depowdering blasting agent.

The angular (polyhedral or cylindrical) particles used in the depowdering process advantageously do not damage the machine components due to their nature. There is therefore no increased wear on machine parts, so that special protection of the machine is not necessary.

Likewise, there is preferably no change in the surface as a result of roughening or compacting, since the particles PA1 or PB1 present in a cubic, cylindrical or prismatic form are less massive.

Due to the angular (polyhedral or cylindrical) shape, there are no compression effects, because the particles are lighter than mineral blasting media, there is less energy input on the surface.

Preferably, the particle PA1 and/or the particle PB1 has a cubic shape, the particle PA1 and/or the particle PB1 has a cylindrical shape, the particle PA1 and/or the particle PB1 has a polyhedral shape, or the particle PA1 and/or the particles PB1 with a prismatic shape each independently have a particle size range in the range from 10 μm to 1000 μm.

The particle PA1 and/or the particle PB1 in the method according to the invention with a cubic shape particularly preferably has a particle size range in the range from 100 μm to 400 μm, very particularly preferably 200 μm to 300 μm.

The particle PA1 and/or the particle PB1 in the method according to the invention with a cylindrical shape particularly preferably has a particle size range in the range from 100 μm to 400 μm, very particularly preferably 200 μm to 300 μm.

The particle PA1 and/or the particle PB1 in the method according to the invention with a prismatic shape particularly preferably has a particle size range in the range from 100 μm to 400 μm, very particularly preferably 200 μm to 300 μm.

The particle PA1 and/or the particle PB1 in the method according to the invention with a polyhedral shape particularly preferably has a particle size range in the range from 100 μm to 400 μm, very particularly preferably 200 μm to 300 μm.

As a rule, an attempt is made to use the smallest possible grain size, for example the particles PA1 and/or PB1, for the plastic blasting agent A used. The smaller the particles used, the lower the mass of the particles. The lower the mass of the particles, the less kinetic energy is transferred when accelerating. The surface of the component should be processed as gently as possible.

If the component surface is damaged anyway, the printing parameters of the 3D printer can be adjusted so that the surface of the additive component is more resistant after the printing process.

Advantageously, the use of preferably abrasion-resistant and polyhedral or cylindrical particles in the depowdering process prevents contamination of the surface from broken blasting media. Due to the higher breaking strength of the particles, there is little abrasion or breakage when the granules are conveyed through the blasting systems or when the particles impact the surface of the additively manufactured components, and therefore no contamination on the surface. This means that no particles are compacted into the surface of the component in the subsequent compaction process of spherical blasting media.

Likewise, the use of abrasion-resistant and polyhedral or cylindrical particles in the depowdering process advantageously prevents subsequent processing steps from being adversely affected. Due to the higher breaking strength of the particles, there is almost no abrasion or breakage when the granulate is conveyed through the blasting systems or when the particles impact the surface of the additively manufactured components, which is then pressed into the component surface in the subsequent compaction process. The coating, infiltration or coloring is therefore not affected.

In particular, the claimed form of the blasting agent used for depowdering does not lead to compaction effects. Because the particles are lighter than mineral blasting media, there is less energy input on the surface. This means that the surface of the component remains open-pored and the ink penetration is not affected.

By using the plastic blasting medium used in the method according to the invention, there is advantageously no uncontrolled breakage due to its material properties. The abrasion, which occurs to a small extent here, has a finely dispersed grain size (<100 µm/ dusty). The grain size and the mass of the dust grains deviate so greatly from the uniform grain size of the blasting agent used that it can be separated in material separators without any problems.

Likewise, the plastic blasting agent S can preferably be produced in the method according to the invention by a polymerization process and then used.

In the method according to the invention, the particle PS1 preferably has a spherical or approximately spherical/oval shape. For the purposes of the present invention, a spherical shape can be a three-dimensional shape without corners and edges or more than 70% of the particles can comprise a shape without corners and edges. The particle PS1 preferably has a shape without corners or with corners whose angles are >90°.

In the process according to the invention, the particle PS1 with a spherical or approximately spherical/oval shape preferably has a particle size range in the range from 10 μm to 1000 μm, particularly preferably 200 μm to 600 μm and very particularly preferably 400 μm to 600 μm.

The particle size range of the foreign particles FA1, FB1 and FS1 in the method according to the invention is preferably in a range from 10 μm to 990 μm, particularly preferably in a range from 10 μm to 100 μm and very particularly preferably in a range from 10 μm to 60 μm.

Advantageously, the plastic blasting agent used here has a uniform grain size. In contrast to common blasting agents, there are no fragments of different grain sizes. The post-processing effort is reduced to a minimum.

The polymers KA1, KB1 and KS1 are preferably selected from the group consisting of polyamides, resins, polyesters, polystyrenes, polyolefins, polyvinyls, rubbers, polyphenylenes, polyethers, polyurethanes, polysaccharides, polyimides, polyacrylates, silicones and blends and copolymers thereof.

In the process according to the invention, the polymers KA1 and KB1 are preferably selected from the group consisting of polyethylene and copolymers of ethylene, such as HDPE (high density polyethylene), MDPE (medium density polyethylene), LLDPE, VLDPE, LDPE (low density polyethylene), ULDP, ethylene hexene copolymers, ethylene octene copolymers, polyisobutylene, ethylene propylene copolymers (EPM), ethylene propylene diene terpolymers (EPDM), EBM (ethylene butyl rubber), EPDM, ethylene vinyl silane copolymers , Ter- or copolymers of acrylic acid (EA), or ethylene with ethylene acrylate and acrylic acid (EAA) or methacrylic acid (EMA), EEA (ethylene ethyl acrylate), EBA (ethylene butyl acrylate), EVA (ethylene vinyl acetate), grafted copolymers of ethylene with maleic anhydride (MAH), polyvinyl chloride (PVC), polyamide 6, polyamide 66, polyamide 12, polyamide 11, polyamide 4, polypropylene and polypropylene copolymers, polyacrylates and polymethacrylates (PMMA), polycarbonate (PC), polybutylene terephthalates ( PBT), Poly ester terephthalate (PET), fluorinated polymeric hydrocarbons, rubber, thermoplastic elastomers (TPE), block copolymers, thermoplastic polyurethanes (TPU) and polyurethanes, thermoplastic polyolefins (TPO), silicone polymers, poly(methyl)methacrylate, polycarbonate, polystyrene, styrene-acrylic-nitrile , polyethylene terephthalate, acrylonitrile butadiene styrene (ABS) and a mixture (blend) of the plastics mentioned.

The polymer KS1 in the process according to the invention is preferably selected from the group consisting of poly(methyl)methacrylate, polycarbonate, polystyrene, styrene-acrylonitrile, polyethylene terephthalate, acrylonitrile-butadiene-styrene (ABS), polyethylene and ethylene copolymers such as HDPE (high density polyethylene), MDPE (medium density polyethylene), LLDPE, VLDPE, LDPE (low density polyethylene), ULDP, ethylene hexene copolymers, ethylene octene copolymers, polyisobutylene, ethylene propylene copolymers (EPM), terpolymers of ethylene propylene diene (EPDM), EBM (ethylene butyl rubber), EPDM, ethylene vinyl silane copolymers, ter- or copolymers of acrylic acid (EA), or ethylene with ethylene acrylate and acrylic acid (EAA) or methacrylic acid (EMA), EEA (ethylene ethyl acrylate), EBA (ethylene butyl acrylate), EVA (ethylene vinyl acetate), grafted copolymers of ethylene with maleic anhydride (MAH), polyvinyl chloride (PVC), polyamide 6, polyamide 66, polyamide 12, polyamide 11, Polyamide-4, Polypropylene and Pol ypropylene copolymers, polyacrylates and polymethacrylates (PMMA), polycarbonate (PC), polybutylene terephthalate (PBT), polyester terephthalate (PET), fluorinated polymeric hydrocarbons, rubber, thermoplastic elastomers (TPE), block copolymers, thermoplastic polyurethanes (TPU) and polyurethanes, thermoplastic polyolefins (TPO ), silicone polymers and a mixture (blend) of the plastics mentioned.

A method for treating a component with blasting agents is particularly preferred, wherein the plastic blasting agent A is a polyamide as polymer KA1, in particular selected from the group consisting of polyamide 6, polyamide 66, polyamide 12, polyamide 11, polyamide 4, polyester terephthalate and as foreign particles FA1 includes glass.

Steps a) to c) are preferably carried out in one plant or in two plants. Steps a), b) and c) can be carried out one after the other or intermediate steps can also be present.

1. a) Bereitstellen eines Bauteils in mindestens einer Strahlanlage, wobei das Bauteil mittels additiver Fertigung erstellt wurde,
2. b) Behandlung des Bauteils mit mindestens einem ersten Strahlmittel, wobei das erste Strahlmittel ein Kunststoffstrahlmittel A umfasst, wobei das Kunststoffstrahlmittel A mindestens einen Partikel PA1 aus mindestens einem Polymer KA1 und mindestens einem Fremdpartikel FA1 umfasst, wobei das Polymer KA1 ausgewählt ist aus der Gruppe, bestehend aus Polyethylen, Polyamid-6, Polyamid-6.6, Polyamid-11, Polyamid-12, Polyamid-4, Polyesterterephthalat sowie Mischungen davon,
3. c) Behandlung des Bauteils mit mindestens einem zweiten Strahlmittel, wobei sich das zweite Strahlmittel vom ersten Strahlmittel unterscheidet, wobei das zweite Strahlmittel ein Kunststoffstrahlmittel S umfasst, wobei das Material des Kunststoffstrahlmittels S ausgewählt ist aus der Gruppe, bestehend aus Polyamiden, Harzen, Polyestern, Polystyrolen, Polyolefine, Kautschuken, Polyvinylchloriden, Polyphenylenen, Polyethern, Polyurethanen, Polyimiden, Polyacrylaten, Silikonen sowie Blends und Copolymeren davon oder wobei das Kunststoffstrahlmittels S mindestens einen Partikel PS1 aus mindestens einem Polymer KS1 und mindestens einem Fremdpartikel FS1 umfasst, wobei das Polymer KS1 ausgewählt ist aus der Gruppe, bestehend aus Polycarbonaten, Polystyrolen, Styrol-Acrylnitrilen, Polyacrylaten oder einer Mischung der genannten Kunststoffe.

A method for treating a component with blasting media is very particularly preferred, comprising the steps:

1. a) Provision of a component in at least one blasting system, whereby the component was created using additive manufacturing,
2. b) Treatment of the component with at least one first blasting agent, the first blasting agent comprising a plastic blasting agent A, the plastic blasting agent A comprising at least one particle PA1 made from at least one polymer KA1 and at least one foreign particle FA1, the polymer KA1 being selected from the group consisting of polyethylene, polyamide 6, polyamide 6.6, polyamide 11, polyamide 12, polyamide 4, polyester terephthalate and mixtures thereof,
3. c) treatment of the component with at least one second blasting agent, the second blasting agent differing from the first blasting agent, the second blasting agent comprising a plastic blasting agent S, the material of the plastic blasting agent S being selected from the group consisting of polyamides, resins, polyesters, Polystyrenes, polyolefins, rubbers, polyvinyl chlorides, polyphenylenes, polyethers, polyurethanes, polyimides, polyacrylates, silicones and blends and copolymers thereof, or wherein the plastic blasting agent S comprises at least one particle PS1 composed of at least one polymer KS1 and at least one foreign particle FS1, the polymer KS1 being selected is from the group consisting of polycarbonates, polystyrenes, styrene-acrylonitriles, polyacrylates or a mixture of the plastics mentioned.

1. a) Bereitstellen eines Bauteils in mindestens einer Strahlanlage, wobei das Bauteil mittels additiver Fertigung erstellt wurde,
2. b) Behandlung des Bauteils mit mindestens einem ersten Strahlmittel, wobei das erste Strahlmittel ein Kunststoffstrahlmittel A umfasst, wobei das Kunststoffstrahlmittel A mindestens einen Partikel PA1 aus mindestens einem Polymer KA1 und mindestens einem Fremdpartikel FA1 umfasst, wobei das Polymer KA1 ausgewählt ist aus der Gruppe, bestehend aus Polyethylen, Polyamid-6, Polyamid-6.6, Polyamid-11, Polyamid-12, Polyamid-4, Polyesterterephthalat sowie Mischungen davon, und wobei der Fremdpartikel FA1 eine Glaskugel mit einem Korngrößenbereich im Bereich von 1 µm bis 100 µm ist,
3. c) Behandlung des Bauteils mit mindestens einem zweiten Strahlmittel, wobei sich das zweite Strahlmittel vom ersten Strahlmittel unterscheidet, wobei das zweite Strahlmittel ein Kunststoffstrahlmittel S umfasst, wobei das Material des Kunststoffstrahlmittels S ausgewählt ist aus der Gruppe, bestehend aus Polyamiden, Harzen, Polyestern, Polystyrolen, Polyolefine, Kautschuken, Polyvinylchloriden, Polyphenylenen, Polyethern, Polyurethanen, Polyimiden, Polyacrylaten, Silikonen sowie Blends und Copolymeren davon oder wobei das Kunststoffstrahlmittels S mindestens einen Partikel PS1 aus mindestens einem Polymer KS1 und mindestens einem Fremdpartikel FS1 umfasst, wobei das Polymer KS1 ausgewählt ist aus der Gruppe, bestehend aus Polycarbonaten, Polystyrolen, Styrol-Acrylnitrilen, Polyacrylaten oder einer Mischung der genannten Kunststoffe.

A method for treating a component with blasting agents is particularly preferred, comprising the steps:

1. a) Provision of a component in at least one blasting system, whereby the component was created using additive manufacturing,
2. b) Treatment of the component with at least one first blasting agent, the first blasting agent comprising a plastic blasting agent A, the plastic blasting agent A comprising at least one particle PA1 made from at least one polymer KA1 and at least one foreign particle FA1, the polymer KA1 being selected from the group consisting of polyethylene, polyamide 6, polyamide 6.6, polyamide 11, polyamide 12, polyamide 4, polyester terephthalate and mixtures thereof, and where the foreign particle FA1 is a glass bead with a particle size range from 1 µm to 100 µm,
3. c) treatment of the component with at least one second blasting agent, the second blasting agent differing from the first blasting agent, the second blasting agent comprising a plastic blasting agent S, the material of the plastic blasting agent S being selected from the group consisting of polyamides, resins, polyesters, Polystyrenes, polyolefins, rubbers, polyvinyl chlorides, polyphenylenes, polyethers, polyurethanes, polyimides, polyacrylates, silicones and blends and copolymers thereof, or wherein the plastic blasting agent S comprises at least one particle PS1 composed of at least one polymer KS1 and at least one foreign particle FS1, the polymer KS1 being selected is from the group consisting of polycarbonates, polystyrenes, styrene-acrylonitriles, polyacrylates or a mixture of the plastics mentioned.

Ideally, the plastic blasting agent A used in the depowdering (step b)) is of the highest possible quality. This means that from the outset there are as few broken foreign particles FA1 of the glass beads in the plastic blasting agent A as possible. In addition, attempts are made to convey the blasting agent as gently as possible through the blasting system used. This is usually done by limiting the pressure to a range of 2 to 7 bar in order to transport the particles with as little energy as possible.

1. 1. Beschichtung oder Umhüllung eines dichteren Fremdpartikels (z.B. Metalle, Mineralien, Glas, Eisen, Stahl, Keramik oder Sonstige) mit Kunststoff, um einen Partikel PA1, PB1 oder PS1 zu erhalten.
2. 2. Produktion eines Kunststoffgranulates mit mehreren kleinen Fremdpartikeln (z.B. Metalle, Mineralien, Glas, Eisen, Stahl, Keramik oder Sonstige) innerhalb des Kunststoffes, um einen Partikel PA1, PB1 oder PS1 zu erhalten.
3. 3. Produktion eines Kunststoffgranulates mit mehreren kleinen Fremdpartikeln aus unterschiedlichen Materialien (z.B. Metalle, Mineralien, Glas, Eisen, Stahl, Keramik oder Sonstige) innerhalb des Kunststoffes, um einen Partikel PA1, PB1 oder PS1 zu erhalten.
4. 4. Produktion eines Kunststoffgranulates mit einem großen Fremdpartikel (z.B. Metalle, Mineralien, Glas, Eisen, Stahl, Keramik oder Sonstige) innerhalb des Kunststoffes, um einen Partikel PA1, PB1 oder PS1 zu erhalten.
5. 5. Produktion eines Kunststoffgranulates mit einer Kombination aus einem großen Fremdpartikel und mehreren kleinen Fremdpartikeln (z.B. Metalle, Mineralien, Glas, Eisen, Stahl, Keramik oder Sonstige) innerhalb des Kunststoffes , wobei der große und die kleinen Partikel nicht aus demselben Material bestehen müssen, um einen Partikel PA1, PB1 oder PS1 zu erhalten.

Due to the often fine structures and geometries that additively manufactured components have, there is usually a requirement to use plastic blasting media or blasting media with the smallest possible grain sizes. Only then can it ideally be guaranteed that the accelerated particles can penetrate fine cracks, holes or other structures in the components. This applies to both the depowdering and the compression process. Since the mass of the individual (plastic) particles decreases the smaller they are, they are shot at the components with less energy. In order to increase the energy that is transferred to the component surface with smaller grain sizes, the mass of the particles can be increased by adding denser materials, ie foreign particles. The blasting agents used in the depowdering or compacting process of the method according to the invention therefore preferably process the component surfaces more effectively despite the smaller grain size. This can preferably be implemented technically in the following ways:

1. 1. Coating or encapsulation of a denser foreign particle (e.g. metals, minerals, glass, iron, steel, ceramics or others) with plastic to obtain a particle PA1, PB1 or PS1.
2. 2. Production of a plastic granulate with several small foreign particles (e.g. metals, minerals, glass, iron, steel, ceramics or others) inside the plastic to obtain a particle PA1, PB1 or PS1.
3. 3. Production of a plastic granulate with several small foreign particles of different materials (e.g. metals, minerals, glass, iron, steel, ceramics or others) inside the plastic to obtain a particle PA1, PB1 or PS1.
4. 4. Production of a plastic granulate with a large foreign particle (e.g. metal, mineral, glass, iron, steel, ceramic or other) inside the plastic to obtain a particle PA1, PB1 or PS1.
5. 5. Production of a plastic granulate with a combination of a large foreign particle and several small foreign particles (e.g. metals, minerals, glass, iron, steel, ceramics or others) within the plastic, whereby the large and the small particles do not have to consist of the same material, to get a particle PA1, PB1 or PS1.

1. a. Ein kubisch oder zylindrisch, extrudiertes Polyamid-6 oder Polyamid-12 Granulat, dem im Compoundierprozess kleine Glasperlen zugemischt werden.
2. b. Ein polyedrisches (vorzugsweise vielkantiges, komplexkantiges) Polyamid-6 oder Polyamid-12 Granulat, dem im Compoundierprozess kleine Eisenperlen zugemischt werden.

For example, in the depowdering process, preference is given to:

1. a. A cubic or cylindrical, extruded polyamide 6 or polyamide 12 granulate to which small glass beads are added during the compounding process.
2. b. A polyhedral (preferably many-edged, complex-edged) polyamide 6 or polyamide 12 granulate to which small iron beads are added during the compounding process.

1. a. Eine Metallkugel, die mit Polystyrol oder Acryl beschichtet wurde
2. b. Eine Keramikkugel, die mit Polystyrol oder Acryl beschichtet wurde

For example, in the densification process, preference is given to:

1. a. A metal sphere that has been coated with polystyrene or acrylic
2. b. A ceramic sphere that has been coated with polystyrene or acrylic

Furthermore, the present invention includes a shaped body produced by the method according to the invention.

A combination system can be implemented thanks to the properties of the plastic blasting agent used, as described above. The depowdering process does not lead to uncontrolled breakage and abrasive abrasion, so unwanted particles can easily be separated in material separators. Carrying over of blasting media (fragments) from the depowdering process into the compacting process is prevented. Nevertheless, the two processes within the meaning of the invention can not only run one after the other in the same system, but also one after the other in two different systems.

• - ein Gehäuse,
• - eine Prozesskammer, die im Gehäuse ausgebildet ist,
• - eine Strahldüse oder mehrere Strahldüsen oder ein Schleuderrad oder mehrere Schleuderrräder, die in der Prozesskammer ausgebildet sind, wobei die eine Strahldüse oder die mehreren Strahldüsen oder das eine Schleuderrad oder die mehreren Schleuderrräder in Verbindung mit mindestens zwei Strahlgutbehältern, enthaltend
  1. a) ein erstes Strahlmittel, wobei das erste Strahlmittel ein Kunststoffstrahlmittel A umfasst, und
  2. b) ein zweites Strahlmittel, wobei sich das zweite Strahlmittel vom ersten Strahlmittel unterscheidet, steht/stehen.

Furthermore, an object of the present invention is a blasting system, comprising

• - a housing,
• - a process chamber formed in the housing,
• - a blast nozzle or several blast nozzles or a blast wheel or several blast wheels, which are formed in the process chamber, wherein the one blast nozzle or several blast nozzles or the one blast wheel or several blast wheels in connection with at least two blasting material containers, containing
  1. a) a first blasting agent, wherein the first blasting agent comprises a plastic blasting agent A, and
  2. b) a second blasting medium, the second blasting medium being different from the first blasting medium, is/are standing.

In addition, a further object of the invention is the use of the blasting system according to the invention in the method according to the invention.

character list

• 1 : In 1 the depowdering process is illustrated as a cross section from the prior art.
• 2 : In the 2 fragments of a blasting agent from the prior art are illustrated in cross section.
• 3 : In 3 the peening process from the prior art is shown in cross section.
• 4 : In the 4 Another prior art depowdered component is shown in cross section before being colored.
• 5 : 5 shows a cross-section of a prior art inking process.
• 6 : In 6 the densification process according to the present invention is illustrated in cross-section.
• 7 : In 7 the coloring process on a compacted surface according to the present invention is illustrated in cross-section.

Detailed character description

1 illustrates the depowdering process as known from the prior art. The surface (1) of an additively manufactured component (2) is shown, the surface (1) of which is blasted using a metallic or mineral blasting agent (3) in order to remove old powder particles. This is a known method in the prior art. Fragments (4) of the blasting agent are also shown.

2 shows that fragments (4) of the blasting agent used for depowdering are present on the surface (1) of the component (2).

In the 3 the shot peening process is illustrated. In this case, the fragments (4) from the first blasting agent enter the surface of the component during the compaction process due to the second blasting agent (5).

4 shows just like that 2 a depowdered component (2) in which the fragments (4) of the blasting agent are present on the surface (2) after the depowdering process. If you want to color this component, as in the 5 shown, the dye (6) not everywhere evenly applied to the surface (1), since the fragments (4) do not absorb the dye.

In the 6a a surface (1) of a component is shown in cross section before compaction. Due to the fact that the less massive polyhedral plastic blasting media were used in the depowdering, there is less or no contamination of the surface (1).

In the 6b the surface is compressed by the spherical particle (7), so that, as in the 6c is illustrated, a glossy surface is created that refracts the light evenly (see reflection arrow).

In the 7a shows a coloring process after depowdering. The image on the left shows the component before coloring, the image on the right after coloring. Due to the non-existent or reduced contamination of the surface (1) of the component with the plastic blasting medium, the dye (6) can penetrate into the rough, unmodified surface (1) of the component (2). The gray surface (1) shows the component (2) after the corresponding coloring process. The same applies to a compressed component, which in the 7b is illustrated. After compaction, the dye can penetrate the surface evenly, but not to the desired depth. This illustrates the partially undesired compression effects during depowdering. The left figure in 7b shows the component (2) before coloring, the right figure after coloring.

determination methods

Table 1 lists the comparison of the test conditions for determining the various Shore hardness values, as specified in the claims and the description. Table 1: Comparison of test conditions for determining SHORE hardness values standard ISO 7619-1 EN ISO 868 DIN 53606 ASTM 2240 Condition (2012-02) [2] (2003-10) [4] (2000-08) [1] (2015-08) [5] sample thickness 6mm 4mm 6mm 6mm layering yes (3 layers) Yes yes (3 layers) Yes measurements 5 5 3 5 measuring distance 6mm 6mm 5mm 6mm holding time 3 s vulcanizates 3s/15s 3s < 1s 15s TPE 1 s according to specification 15s load 1kg SHORE A 5kg SHORE D A: 12.5N ± 0.5 D: 50.0N ± 0.5 A: 12.5N ± 0.5 D: 50.0N ± 0.5 1 kg hardness specification 54 Shore A 3 s 54 Shore A15 s A/15:54 A/1:54 54 Shore A 54 Shore A 15s A/54/1 A/54/15

examples

1. 1. Entpulverung von additiv gefertigten Bauteilen durch das oben beschriebene Kunststoffstrahlmittel. (Bei dem eingesetzten Kunststoffstrahlmittel kann es sich auch um Kunststoffstrahlmittel mit Füllungen und/oder sonstige Partikel handeln, die mit Kunststoff ummantelt wurden.)
2. 2. Verdichtung des Bauteils durch Polystyrolbeads.
3. 3. Färbung im Tauchverfahren oder Färbung in einer Farbstofflösung.

In the examples described below, the treatment of a component with blasting agents is described in two steps.

1. 1. Depowdering of additively manufactured components using the plastic blasting agent described above. (The plastic blasting media used can also be plastic blasting media with fillings and/or other particles that have been coated with plastic.)
2. 2. Densification of the component with polystyrene beads.
3. 3. Dyeing by immersion or dyeing in a dye solution.

An example of the examined process is described below:

1. Depowdering process

The additively manufactured components were de-powdered using a plastic blasting agent.

• - Kornform: Zylindrisch
• - Korngröße: Einheitlich 400µm
• - Materialeigenschaften: Polyamid-6, extrudiert, mit Glaskugeln (<100µm) gefüllt

Properties of the abrasive:

• - Grain shape: cylindrical
• - Grain size: Uniform 400 µm
• - Material properties: Polyamide-6, extruded, filled with glass beads (<100µm).

• - Strahlzeit von 5 bis 30 Minuten
• - Strahldruck von 2 bis 5 Bar
• - Abblasdruck (Reinigungsdüsen) 6 Bar
• - Bauteilmenge im Prozess von einem Bauteil bis 1000 Bauteile

Process parameters:

• - Blasting time from 5 to 30 minutes
• - Jet pressure from 2 to 5 bar
• - Blow-off pressure (cleaning nozzles) 6 bar
• - Amount of components in the process from one component to 1000 components

2. Densification process

The depowdered components were then compacted. Polystyrene balls are accelerated in the blasting nozzle of an injector blasting cabin with 5 bar compressed air and blasted onto the component surface. When the spherical polystyrene particles hit the surface, a compression effect occurs.

• - Kornform: Sphärisch/Kugelförmig
• - Korngröße: Korngrößenverteilung von 400 - 600µm
• - Materialeigenschaften: Polystyrol (polystyrenic copolymer)

Properties of the abrasive:

• - Grain shape: Spherical/Spherical
• - Grain size: Grain size distribution from 400 - 600 µm
• - Material properties: polystyrene (polystyrenic copolymer)

• - Strahlzeit von 10-20 Minuten
• - Strahldruck bei 5 Bar
• - Abblasdruck (Reinigungsdüsen) 6 Bar

Process parameters:

• - Blasting time of 10-20 minutes
• - Jet pressure at 5 bar
• - Blow-off pressure (cleaning nozzles) 6 bar

3. Staining/Infiltration Process

• - Färbetemperatur: 115°
• - Färbezeit: Gesamtprozess ca. 3 Stunden, abhängig von Material und Bauteilmenge, Umgebungsbedingungen.
• - Trocknungszeit: Durchschnittlich 30 Minuten, abhängig von Geometrie und Bauteilmenge.
• - Farbe/Farbrezept: Unterschiedlich, vor Allem Rezepturen die generell besonders problematisch sind.

The compacted components were then colored.

• - Dyeing temperature: 115°
• - Dyeing time: Total process approx. 3 hours, depending on material and component quantity, ambient conditions.
• - Drying time: 30 minutes on average, depending on geometry and component quantity.
• - Color/color recipe: Different, especially recipes that are generally particularly problematic.

In combination, the processes meet all requirements. The problems that arise with the commonly used glass blasting agent for depowdering do not occur. The color quality on the finished component is significantly better than when using glass blasting media in the depowdering process.

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• EP 3444073 [0009]
• EP 1034890 A2 [0010]

Claims (19)

Method for treating a component with blasting agents, comprising the steps: a) Provision of a component in at least one blasting system, with the component preferably being created by means of additive manufacturing, b) treatment of the component with at least one first blasting agent, the first blasting agent comprising a plastic blasting agent A, c) Treatment of the component with at least one second blasting agent, the second blasting agent being different from the first blasting agent. Method for treating a component with blasting agents according to claim 1 , wherein the plastic blasting agent A comprises at least one particle PA1 made of at least one polymer KA1 and at least one foreign particle FA1. Method for treating a component with blasting agents according to claim 1 or 2 , wherein the first blasting agent additionally comprises a plastic blasting agent B, wherein the plastic blasting agent B comprises at least one particle PB1 of at least one polymer KB1 and at least one foreign particle FB1. Method for treating a component with blasting agents according to one of Claims 1 until 3 , wherein the polymer KA1 and/or KB1 has a Shore hardness of 10 Shore A to 95 Shore D. Method for treating a component with blasting agents according to one of Claims 1 until 4 , wherein the foreign particles FA1 and FB1 are selected from the group consisting of metals, minerals, soot particles, carbon fibers, paint particles, ceramics, polymers, alloys or glasses. Method for treating a component with blasting agents according to one of Claims 1 until 5 , wherein the second blasting agent comprises a plastic blasting agent S and the material of the plastic blasting agent S is selected from the group consisting of polyamides, resins, polyesters, polystyrenes, polyolefins, polyvinylene, rubbers, polyphenylenes, polyethers, polyurethanes, polysaccharides, polyimides, polyacrylates, silicones and blends and copolymers thereof. Method for treating a component with blasting agents according to one of Claims 1 until 5 , wherein the second blasting agent comprises a plastic blasting agent S, which comprises at least one particle PS1 made of at least one polymer KS1 and at least one foreign particle FS1. Method for treating a component with blasting agents according to claim 7 , wherein the foreign particle FS1 is selected from the group consisting of metals, minerals, soot particles, carbon fibers, paint particles, ceramics, polymers, alloys or glasses. Method for treating a component with blasting agents according to one of Claims 1 until 8th , wherein the plastic blasting agent A, B and/or the plastic blasting agent S is produced by a compounding process, an injection molding process, precipitation polymerization or an extrusion process. Method for treating a component with blasting agents according to one of Claims 1 until 9 , wherein the particle PA1 and/or the particle PB1 has a cubic, prismatic, polyhedral or cylindrical shape. Method for treating a component with blasting agents according to one of Claims 1 until 10 , wherein the particle PS1 has a spherical or approximately spherical/oval shape. Method for treating a component with blasting agents according to one of Claims 1 until 11 , wherein the particle PA1 and/or the particle PB1 having a cubic shape, wherein the particle PA1 and/or the particle PB1 having a cylindrical shape, wherein the particle PA1 and/or the particle PB1 having a polyhedral shape, or wherein the particle PA1 and/or PB1 with a prismatic shape each independently has a particle size range in the range from 10 μm to 1000 μm. Method for treating a component with blasting agents according to one of Claims 1 until 12 , wherein the particle PS1 with a spherical or approximately spherical/oval shape has a particle size range in the range from 10 μm to 1000 μm. Method for treating a component with blasting agents according to one of Claims 1 until 13 , The particle size range of the foreign particles FA1, FB1 and/or FS1 being in a range from 1 μm to 990 μm. Method for treating a component with blasting agents according to one of Claims 1 until 14 , wherein the polymers KA1, KB1 and KS1 are selected from the group consisting of polyamides, resins, polyesters, polystyrenes, polyolefins, polyvinylene, rubbers, polyphenylenes, polyethers, polyurethanes, polysaccharides, polyimides, polyacrylates, silicones and blends and copolymers thereof. Method for treating a component with blasting agents according to one of Claims 1 until 15 , wherein the plastic blasting agent A comprises a polyamide as the polymer KA1 and glass as the foreign particle FA1. Method for treating a component with blasting agents according to one of Claims 1 until 16 , where steps a) to c) are carried out in one system or two systems. Shaped body produced by the method according to one of Claims 1 until 17 . Blasting system, comprising: - a housing, - a process chamber formed in the housing, - a blast nozzle or several blast nozzles or a blast wheel or several blast wheels, which are formed in the process chamber, wherein the one blast nozzle or the several blast nozzles or the one blast wheel or the several blast wheels in connection with at least two blasting material containers, containing a) a first blasting agent, wherein the first blasting agent comprises a plastic blasting agent A, and b) a second blasting medium, the second blasting medium being different from the first blasting medium, is/are standing.

Images