A kind of preparation method of copper base alloy sliding surface bearing
Technical field
The present invention relates to a kind of preparation method of copper base alloy sliding surface bearing, particularly relate to a kind of improve composition and there is the preparation method of the copper base alloy sliding surface bearing of wearing layer.
Background technology
Copper is that the mankind find and use one of metal the earliest, is characterized in having very high conduction, heat conductivility and good plasticity, is only second to gold and silver and occupies the 3rd at these aspect of performances.Although its life-span is long, still continuing to make progress in metallurgy of copper.Fine copper has face-centered cubic character, and without allotropic transformation, plasticity is high and intensity is low, directly should not be used as structured material, how as the raw material preparing copper alloy.
The intensity of fine copper is not high, therefore will meet the requirement of structural part, must carry out the alloying of copper.The object of the alloying of copper, mainly strengthens mutually in order to realize solution strengthening, ageing strengthening and surplus, thus obtains high strength copper alloy.Sorting technique traditionally, usually by the in addition rough segmentation of red copper, brass, bronze, the large series of copper-nickel alloy four.Red copper is fine copper and adds other element a small amount of, brass is called using zinc as the copper alloy of main added elements, the basis of binary brass is added the elements such as Al, Fe, Si, Mn, Pb, Ni and forms special brass, be called aluminum brass, iron brass, silicon brass, manganese brass, leaded brass, nickel brass by the main difference of adding element of interpolation second.Be not called bronze with zinc for main added elements, can be divided into tinbronze, xantal, lead bronze, berylliumbronze etc. again by the difference of main added elements, they have the intensity higher than market brass, hardness, corrosion resistance and good castability.Copper-nickel alloy is called for main added elements with nickel.Copper and its alloy, with one of excellent heat conduction electrical property, high corrosion resisting property, good castability and mechanical property and the suitable intensity important foundation material becoming modern industry, occupies critical role in national economy.Copper alloy is stranded the performance with high strength and high conductivity heat conduction and wear-and corrosion-resistant and becomes the indispensable metallic substance of modern industry.
Along with the development that modern science and technology are maked rapid progress, the performance of modern industry to copper alloy is had higher requirement, as high precision, high-performance and all many-sides such as economical and practical.At present, the research of zinc-aluminum based alloy (ZA) application has achieved gratifying achievement, and its superior mechanical property and good Production Practice of Casting Technologies and machinability attract people's attention, and break, have the trend replacing copper alloy gradually in high-strength alloy side.But this alloy is the same with any one alloy series, also come with some shortcomings part, wherein some is because the person's character of alloy determines, should not improve, as: easily produce gravity segregation, there is certain shrinkage porosite tendency, pulling defect is easily produced during sand mold casting, thermal expansivity is larger, there is aging potentially dangerous etc., and ZA alloy to be used for the problem of conducting plates material be poorly conductive, the application of ZA alloy will mainly concentrate on oneself part of knowing of the wearing piece of periodic replacement and consumable accessory or some other length of service from now on.Thus ZA alloy still can not replace copper alloy completely in some aspects, over a period to come, is still necessary to develop Novel copper alloy.
Copper based wear-resistant alloy traditionally based on all kinds of bronze, brass, with they be processed into section bar or cast product is applied.As plate, band, pipe, rod, the wire rod good combination property of berylliumbronze, thermal conductivity is good, after thermal treatment, even intensity, wear resistant corrosion resistant, castibility is good, be suitable for manufacturing various wear part and at a high speed, the bearing, the lining that work under high pressure and high temperature, but berylliumbronze because of it is expensive, beryllium is malicious public hazards and yield rate low and the production of this alloy and use are restricted.The BeO powder that berylliumbronze is released in the operation such as melting, processing has very large harm to human body, and environmental protection equipment also will carry out investment.Titanium bronze also has the advantages such as good wear resistance, and is used as snappiness, high strength, the various electronic components of high abrasion, small-sized precision gear and various bearing, but titanium metal also costly.The crystallization range of xantal is very little, good fluidity, dense structure, but its linear shrinkage ratio is large, if gating system arranges unreasonable, can crack.
Because copper base alloy has certain limit to the raising of intensity while maintenance electric-conductivity heat-conductivity high, and complex intensifying can play the synergy of matrix electric-conductivity heat-conductivity high and strengthening material simultaneously, has again very large design freedom.Therefore in recent ten years, beautiful, Deng developed country is very active to developing of this kind of material, China's starting then relatively evening.Complex intensifying obviously can not reduce the conductivity of Copper substrate, and can also improve room temperature and the high-temperature behavior of matrix.Its ultimate principle is: according to the requirement of design of material performance, suitable wild phase (one or more) is selected to add matrix, while maintenance matrix highly conc, give full play to the strengthening effect of wild phase, make the conductivity of material and intensity reach good mating.According to the form of wild phase, high-strength high conductivity heat-conducting copper-based composite material can be divided into: granule reinforced copper base composite material and fiber reinforcement Cu-base composites.Particulate reinforced composite to refer in Copper substrate artificially or by the second phase particles of certain technique in-situ preparation Dispersed precipitate.Second phase particles hinders the motion of dislocation, thus improves the intensity of material, as A1203/Cu matrix material, TiC/Cu matrix material.Fiber reinforcement Cu-base composites refers in Copper substrate, adds the fiber of rule oriented arrangement or the second-phase fiber by directed proper alignment between certain technique in-situ preparation homogeneous phase artificially, fiber makes dislocation motion resistance increase, thus metallic matrix is strengthened, as C/Cu, Fe/Cu original position deformed composite material.Copper base compound profit material also can be used for various friction condition and has the occasion of high strength and high conductivity heat conduction requirement, as electrode brush etc.The shortcoming of Cu-base composites is exactly need special equipment, and because the wettability of fiber and Copper substrate is poor, thus preparation technology's difficulty, cost is higher.
The wearing and tearing of usual material are categorized as by wear mechanism: 1. adhesive wear, 2. abrasive wear, 3. fatigue wear, 4. corrosive wear.
The adhesive wear of material lost efficacy and referred in friction process, is produced from the state on friction pair material surface: given birth to adhesion shearing effect, make inefficacy that is that friction material surface comes off or that cause to the transfer of antithesis surface, it is characterized in that having sent out first the migration that friction pair material is surperficial to another by a surface or ask each other, adhesion node intensity is higher, shear the degree of depth darker, wear and tear more serious, until there is adhesion wear.The possibility that adhesive wear inefficacy occurs is relevant with the material of friction pair material.More easily there is adhesive wear in the friction pair that the elastic-plastic material (as same metal) that chemical property is similar, mutual solubility is good is formed; , owing to not yet being formed at starting moment oil film, very likely there is adhesive wear and lost efficacy in the heavy-duty machinery of some liquid hydrodynamic lubrications.Improve lubrication, especially adopting has the solid lubricant of self-lubricating property. or coupling friction pair material is the main path preventing or avoid adhesive wear to lose efficacy again.
Abrasive wear lost efficacy and refers to that the friction table that the hard protrusion thing by extraneous grit or couple table causes in friction process and material chop and come off or inefficacy that viscous deformation causes; cause the wearing and tearing of component failure to come from abrasive particle to the plow effect on friction pair material surface and the crimp of kniting the brows property, exist hard abrasive well produce on friction surface obvious abrasive particle scratch vestige be the prerequisite judging abrasive wear.The wear out failure of this form is extensively present in the more severe mechanical means of all kinds of envrionment conditions, sometimes be not due to the reason in design, having certain sporadic, is reduce the main path that sporadic abrasive wear lost efficacy by strengthening the maintenance of equipment and lubricating management.
Fatigue wear lost efficacy and referred to that surface of friction pair was under the contact stress effect of circulation change, peels off formation pit and cause losing efficacy due to fatigue of materials.In general, even under good lubricating condition, the fatigue wear of surface of friction pair lost efficacy still inevitable, but mostly showed as the Surface fatigue wear of non scalable.The fatigue wear of parts lost efficacy and mainly came from the Surface fatigue wear of extendability, its process comprises the effect (containing rolling resistance) due to periodically variable normal load and tangential friction force, at friction pair subsurface stress raiser germinating tiny crack, crack propagation, to surface, forms wearing and tearing.It is characterized in that the pit that there is acne plaque-like on friction surface.The wearing and tearing of this form and load character and mode of motion have substantial connection.Impurity in friction pair material, hole, dislocation and internal stress etc., owing to destroying the continuity of matrix, under the effect of pulsating stress, form stress raiser, easily produce fatigue cracking and cause wearing and tearing.
Corrosive wear was lost efficacy and was referred in friction process, friction pair material and surrounding medium there occurs chemistry or electrochemistry phase watt acts on, this effect aggravation, the wear process of material and the inefficacy caused, it is characterized in that chemical corrosion and mechanical wear exist simultaneously and promotes mutually, depositing corrosive medium between friction pair is the prerequisite that corrosive wear was lost efficacy, and the abrasive dust of formation should be the product of friction pair material and media chemistry effect.
At present, the formation of bearing high-abrasive material tissue is distributed on hard matrix primarily of soft disperse phase, improve the wear resisting property of material, particle size and the distribution of disperse phase must be improved, improve the performance of matrix simultaneously, existing alloy also also exists organizes inadequate refinement, the shortcoming that matrix strength is lower, limits the work-ing life of oil engine centre bearer material.The Working environment of bearing also requires the coating that wear resisting property is more excellent simultaneously.
Summary of the invention
The object of the present invention is to provide a kind of preparation method of copper base alloy sliding surface bearing.
The present invention is achieved by the following technical solutions: a kind of sliding surface bearing, is characterized in that, it comprises alloy bulk and wear-resistant coating, and wherein alloy bulk is made up of the component of following weight percent:
Copper 76 ~ 83 wt%
Rare earth metal 0.6 ~ 1.9 wt%
Tin 5.5 ~ 7.8 wt%
Silver 0.1 ~ 2.3 wt%
Surplus is plumbous;
Wherein, the weight percent of described rare earth metal consists of:
Cerium 46 ~ 49 wt%
Lanthanum 17 ~ 31 wt%
Praseodymium 4 ~ 7 wt%
Neodymium 11 ~ 18 wt%
Surplus is other rare earth element;
The component composition of the following weight percent of wear-resistant coating:
TiO
2 25~55wt.%
NiCrBSiFe 9~27wt.%
Cr
2O
320~38wt.%
Sn 2~3 wt%
C-Ni 10 ~ 15wt.%, wherein Ni weight content is 60 ~ 75%
The preparation method of above-mentioned copper base alloy sliding surface bearing, comprises the following steps:
A, prepare bearing metal body
(1) each feed composition is taken according to the said ratio of alloy bulk;
(2), before melting outside copper removal, other object need putting into body of heater all toasts 1 hours to prevent from bringing steam at fusion process at 200 DEG C of baking ovens;
(3) baking material is complete puts into medium-frequency induction furnace by electrolytic copper, tin and lead, first with low-power heating 3 ~ 5 minutes, then add high-power make above-mentioned raw materials melt after add silver and rare earth metal again, then melting 20 ~ 30min at the temperature of 1150 ~ 1250 DEG C, fusion process stirs 3 ~ 5 times, mixes completely to reach;
(4) adopt jet shaper, after again being melted by above-mentioned alloy, carry out the supersonic airstream spray deposition process of alloy with ultrasonic nebulization jet nozzle: atomizing gas is nitrogen, gas flow 650L/min; The distance of spray deposition is 40cm, and spray deposition terminates obtained copper based wear-resistant alloy;
(5) bearing metal body is obtained through machining as requested;
B, prepare wear-resistant coating
(6) each feed composition is taken according to the said ratio of wear-resistant coating;
(7) said components powder is carried out mechanically mixing, the powder mixing machine time is not less than 30 minutes;
(8) sandblasting is carried out to the surface of bearing metal body;
(9) powder after above-mentioned mechanically mixing is sprayed as feeding, form high temperature and high speed plasma jet by plasma gun, select Ar airshed 15L/min, H
2airshed 5L/min, electric current 600A, spray power is about 39Kw, spray distance 100mm, after powder feeding rate 10g/min powder feeding air propels mixed powder enters plasma jet, mixed powder is rapidly heated to melting or semi-melting state, and is accelerated by plasma jet, form the spraying particle bundle flying to matrix surface, particle beam strikes through matrix surface; Each spraying at least 10min interval time, each coating thickness, not higher than 20 μm, treats that matrix surface temperature sprays lower than 200 DEG C next time again;
(10) coating of the final acquisition about 50 μm of spraying repeatedly, finally obtained sliding surface bearing.
Technique effect of the present invention and advantage are: first, the invention provides high-performance copper based wear-resistant alloy body, this alloy is owing to the addition of the rare earth metals such as cerium, lanthanum, praseodymium, and after have employed this preparation technology's preparation of jet deposition, its matrix strength, hardness and self lubricity improve further, thus compare traditional casting copper base alloy and be significantly improved on wear resisting property, wear rate then significantly reduces; And employ appropriate silver in alloy material, not only improve the corrosion resistance of alloy, and reduce the size of Cu-Sn phase in alloy, carry heavy alloyed shear strength.Secondly, coated material of the present invention, contains ceramic matrix TiO
2, particle is less and have the Cr of extreme hardness, wear resistance
2o
3as enhanced granule, the self-fluxing alloy NiCrBSiFe of bonding strength between matrix material, toughness can be improved, there is the lubricant C-Ni of good solid lubrication effect, the wear resistance of coating, cohesive strength, splitting resistance can be significantly improved, and effectively reduce the frictional coefficient of coating.
Embodiment
The technique means realized to make the present invention, creation characteristic, reaching object and effect is easy to understand, below in conjunction with specific embodiment, setting forth the present invention further.
Embodiment 1:
A, prepare bearing metal body
(1) each feed composition of alloy bulk is taken according to following proportioning,
Copper 76 wt%
Rare earth metal 0.6 wt%
Tin 7.8 wt%
Silver 2.3 wt%
Surplus is plumbous;
Wherein, the weight percent of described rare earth metal consists of:
Cerium 46 wt%
Lanthanum 17 wt%
Praseodymium 4 wt%
Neodymium 18 wt%
Surplus is other rare earth element;
(2), before melting outside copper removal, other object need putting into body of heater all toasts 1 hours to prevent from bringing steam at fusion process at 200 DEG C of baking ovens;
(3) baking material is complete puts into medium-frequency induction furnace by electrolytic copper, tin and lead, first with low-power heating 3 minutes, then add high-power above-mentioned raw materials is melted after add silver and rare earth metal again, then melting 30min at the temperature of 1150 DEG C, fusion process stirs 5 times, mixes completely to reach;
(4) adopt jet shaper, after again being melted by above-mentioned alloy, carry out the supersonic airstream spray deposition process of alloy with ultrasonic nebulization jet nozzle: atomizing gas is nitrogen, gas flow 650L/min; The distance of spray deposition is 40cm, and spray deposition terminates obtained copper based wear-resistant alloy;
(5) bearing metal body is obtained through machining as requested;
B, prepare wear-resistant coating
(6) each feed composition of wear-resistant coating is taken according to following proportioning;
TiO
2 25 wt.%
NiCrBSiFe 9 wt.%
Cr
2O
320 wt.%
Sn 2 wt.%
C-Ni 15 wt.%, wherein Ni weight content is 60%
(7) said components powder is carried out mechanically mixing, the powder mixing machine time is not less than 30 minutes;
(8) sandblasting is carried out to the surface of bearing metal body;
(9) powder after above-mentioned mechanically mixing is sprayed as feeding, form high temperature and high speed plasma jet by plasma gun, select Ar airshed 15L/min, H
2airshed 5L/min, electric current 600A, spray power is about 39Kw, spray distance 100mm, after powder feeding rate 10g/min powder feeding air propels mixed powder enters plasma jet, mixed powder is rapidly heated to melting or semi-melting state, and is accelerated by plasma jet, form the spraying particle bundle flying to matrix surface, particle beam strikes through matrix surface; Each spraying at least 10min interval time, each coating thickness, not higher than 20 μm, treats that matrix surface temperature sprays lower than 200 DEG C next time again;
(10) coating of the final acquisition about 50 μm of spraying repeatedly, finally obtained sliding surface bearing.
Embodiment 2
A, prepare bearing metal body
(1) each feed composition of alloy bulk is taken according to following proportioning,
Copper 79 wt%
Rare earth metal 1.2 wt%
Tin 6.3 wt%
Silver 1.7 wt%
Surplus is plumbous;
Wherein, the weight percent of described rare earth metal consists of:
Cerium 47 wt%
Lanthanum 21 wt%
Praseodymium 5 wt%
Neodymium 15 wt%
Surplus is other rare earth element;
(2), before melting outside copper removal, other object need putting into body of heater all toasts 1 hours to prevent from bringing steam at fusion process at 200 DEG C of baking ovens;
(3) baking material is complete puts into medium-frequency induction furnace by electrolytic copper, tin and lead, first with low-power heating 4 minutes, then add high-power above-mentioned raw materials is melted after add silver and rare earth metal again, then melting 25min at the temperature of 1200 DEG C, fusion process stirs 4 times, mixes completely to reach;
(4) adopt jet shaper, after again being melted by above-mentioned alloy, carry out the supersonic airstream spray deposition process of alloy with ultrasonic nebulization jet nozzle: atomizing gas is nitrogen, gas flow 650L/min; The distance of spray deposition is 40cm, and spray deposition terminates obtained copper based wear-resistant alloy;
(5) bearing metal body is obtained through machining as requested;
B, prepare wear-resistant coating
(6) each feed composition of wear-resistant coating is taken according to following proportioning;
TiO
2 35 wt.%
NiCrBSiFe 13 wt.%
Cr
2O
325 wt.%
Sn 2.4 wt%
C-Ni 13 wt.%, wherein Ni weight content is 69%
(7) said components powder is carried out mechanically mixing, the powder mixing machine time is not less than 30 minutes;
(8) sandblasting is carried out to the surface of bearing metal body;
(9) powder after above-mentioned mechanically mixing is sprayed as feeding, form high temperature and high speed plasma jet by plasma gun, select Ar airshed 15L/min, H
2airshed 5L/min, electric current 600A, spray power is about 39Kw, spray distance 100mm, after powder feeding rate 10g/min powder feeding air propels mixed powder enters plasma jet, mixed powder is rapidly heated to melting or semi-melting state, and is accelerated by plasma jet, form the spraying particle bundle flying to matrix surface, particle beam strikes through matrix surface; Each spraying at least 10min interval time, each coating thickness, not higher than 20 μm, treats that matrix surface temperature sprays lower than 200 DEG C next time again;
(10) coating of the final acquisition about 50 μm of spraying repeatedly, finally obtained sliding surface bearing.
Embodiment 3
A, prepare bearing metal body
(1) each feed composition of alloy bulk is taken according to following proportioning,
Copper 83 wt%
Rare earth metal 1.9 wt%
Tin 5.5 wt%
Silver 0.1 wt%
Surplus is plumbous;
Wherein, the weight percent of described rare earth metal consists of:
Cerium 49 wt%
Lanthanum 31 wt%
Praseodymium 7 wt%
Neodymium 11 wt%
Surplus is other rare earth element;
(2), before melting outside copper removal, other object need putting into body of heater all toasts 1 hours to prevent from bringing steam at fusion process at 200 DEG C of baking ovens;
(3) baking material is complete puts into medium-frequency induction furnace by electrolytic copper, tin and lead, first with low-power heating 5 minutes, then add high-power make above-mentioned raw materials melt after add silver and rare earth metal again, then melting 20min at the temperature of 1250 DEG C, fusion process stirs 3 ~ 5 times, mixes completely to reach;
(4) adopt jet shaper, after again being melted by above-mentioned alloy, carry out the supersonic airstream spray deposition process of alloy with ultrasonic nebulization jet nozzle: atomizing gas is nitrogen, gas flow 650L/min; The distance of spray deposition is 40cm, and spray deposition terminates obtained copper based wear-resistant alloy;
(5) bearing metal body is obtained through machining as requested;
B, prepare wear-resistant coating
(6) each feed composition of wear-resistant coating is taken according to following proportioning;
TiO
2 55 wt.%
NiCrBSiFe 9 wt.%
Cr
2O
338 wt.%
Sn 3 wt.%
C-Ni 10 wt.%, wherein Ni weight content is 75%
(7) said components powder is carried out mechanically mixing, the powder mixing machine time is not less than 30 minutes;
(8) sandblasting is carried out to the surface of bearing metal body;
(9) powder after above-mentioned mechanically mixing is sprayed as feeding, form high temperature and high speed plasma jet by plasma gun, select Ar airshed 15L/min, H
2airshed 5L/min, electric current 600A, spray power is about 39Kw, spray distance 100mm, after powder feeding rate 10g/min powder feeding air propels mixed powder enters plasma jet, mixed powder is rapidly heated to melting or semi-melting state, and is accelerated by plasma jet, form the spraying particle bundle flying to matrix surface, particle beam strikes through matrix surface; Each spraying at least 10min interval time, each coating thickness, not higher than 20 μm, treats that matrix surface temperature sprays lower than 200 DEG C next time again;
(10) coating of the final acquisition about 50 μm of spraying repeatedly, finally obtained sliding surface bearing.
Test above-mentioned multiple embodiment, the dry friction and wear rate that the present invention obtains bearing shell body is less than 15 × 10
-12m
3/ m, coating average microhardness reaches 658Mpa.
Above-mentioned example, only for technical conceive of the present invention and feature are described, its object is to person skilled in the art can be understood content of the present invention and implement according to this, can not limit the scope of the invention with this.All equivalent transformations of doing according to spirit of the present invention or modification, all should be encompassed within protection scope of the present invention.