JPH01247538A - Manufacture of sliding material - Google Patents

Abstract

PURPOSE:To manufacture a sliding material containing lubricating components uniformly in large quantities by mixing a powder of Al or Al alloy and powders of Sn, Pb, Bi, In, etc., together with an organic or inorganic binder, agitating the above, and then sintering the resulting mixture. CONSTITUTION:A powder of Al or Al alloy as a base metal and powders of one or more elements among Sn, Pb, Bi, and In as lubricating components are mixed together with a binder consisting of an organic or inorganic material, and these are agitated. As the above organic binder, PVA, stearic acid, aluminum phosphate, etc., can be used, and further, alumina sol, sodium silicate, graphite, colloidal silica, etc., can be used as the above inorganic binder. By the above agitation, a coating layer of the above binder is formed on the surface of the above powders, by which uniformly mixed state can be maintained. The resulting mixture is predried and packed into a metal mold, which is sintered to undergo integration. By this method, the high-quality sliding material, such as bearing, in which lubricating components are dispersedly contained uniformly in sufficiently high additive quantities can be obtained.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Field of Application) The present invention relates to a method for manufacturing sliding materials such as bearing materials, and in particular, the present invention relates to a method for manufacturing sliding materials such as bearing materials. The present invention relates to a method for producing a sliding material containing a lubricating component.

(Prior art) Aluminum (A)-based sliding materials used in bearings, etc. include tin (Sn), lead (Pb), bismuth (Bi),
Those containing a lubricating component made of a heavy metal such as indium (In) are known.

Conventionally, casting has been the mainstream method for manufacturing such sliding materials. However, with AI as the base metal, 3
There is a large difference in specific gravity from alcohol components such as n, pb, 3i, in, etc., and heavy segregation tends to occur, so it is difficult to manufacture materials with a large amount of lubricant added using this casting method, and it is difficult to produce materials with a large amount of lubricant added. Limited to the manufacture of materials.

Therefore, a powder sintering method has been attempted as a method of increasing the amount of lubricant added. In the powder sintering method, A powder as a base metal and Sn, Pb, Bi, In as lubricating components are used.
This method involves mixing, stirring, and sintering powders such as powders, etc., and then sintering them to form a single body.It is possible to add a larger amount of lubricating components than with the casting method.

(Problems to be Solved by the Invention) However, even in the powder sintering method, uneven distribution of lubricating components occurs due to differences in specific gravity during the powder mixing process, making it difficult to obtain a sufficiently high addition amount desired for bearings and the like.

The present invention was made in view of the above circumstances, and is a sliding material that can easily and freely adjust a sufficiently high amount of lubricating components without causing uneven distribution of the lubricating components by a powder sintering method. The purpose is to provide information on manufacturing methods for materials.

[Structure of the invention]

(Means and effects for solving the problems) The present invention provides powders of AI or its alloys, Sn, Pb,
¥f@ refers to mixing and stirring one or more powders selected from Bi and in with a binder made of an organic or inorganic material, and then sintering and integrating the powder.

The present invention has been made based on the following findings. That is, powder of AI or A1 alloy as a base metal and Sn as a lubricating component.

Pb, 3i, or tn powders tend to slip on the interface between the powders in their original state, and due to the difference in weight, they are unevenly separated vertically during stirring and mixing. In particular, since the content of the base metal is high, the particle size of AI or He1 alloy powder is increased, and Sn
, Pb, Bi, In, etc., when the particle size is reduced and mixed, the weight 1 is large and the particle size is small, such as Sn, pb, Bi,
In and other powders fall through the gaps between the aluminum or AI gold alloy powders and accumulate in the lower part, and only AI or one alloy tends to exist in the upper part.

Therefore, it is believed that if adhesiveness is imparted to the powder interface, the falling movement of the heavy powder can be suppressed and the uneven distribution of the heavy powder at the bottom can be prevented.In the present invention, the base metal powder and the rA lubricating component powder are By mixing and stirring with an inorganic binder, a binder coating layer is formed on the powder surface. With this binder, for example, fine Sn, Pb
.

The powders such as 3i and ln adhere to each other, and a uniform mixed state is maintained as a whole. That is, Sn and Pb are heavier due to the difference in specific gravity during the mixing process.

It is possible to prevent powders such as 3i and in from being unevenly distributed in some areas,
Or it can be significantly suppressed by v1.

The binder only needs to be able to prevent uneven distribution during powder mixing before sintering, and various organic or inorganic binders can be used.

Examples of organic binders include polyvinyl alcohol (
PVA), stearic acid, aluminum phosphate, etc. can be applied.

Further, as the inorganic binder, for example, alumina sol, sodium silicate, graphite, colloidal silica, etc. can be used.

Note that alumina sol is suitable as the binder used in the present invention because it crystallizes upon drying and exhibits a strong powder binding effect.

The binder-added powder is pre-dried (in the case of alumina sol, dried at 150° C. for several hours) or directly filled into a mold and sintered. This makes it possible to obtain high-quality bearing materials in which the lubricating components are uniformly dispersed, with the added amount of the rIJ lubricating components being freely controlled.

The m rib material obtained by the method of the present invention can be used not only for bearings but also for bearings.
It can be widely applied as various sliding members for rotating or parallel action.

(Example) A1 powder (99
, 7wt%AJ) and an average particle size of 5μ as a lubricant component.
m of Pb coarse powder were mixed at a weight ratio of 85:15, and alumina sol (containing alumina hydrate: 1110 wt%) as a binder was added thereto at a ratio of 15 wt% of the total acid, and stirred for about 30 minutes. This allows AI powder and p
b A uniform coating layer of alumina sol was formed on the surface of the coarse powder.

FIG. 1(A) shows a mixed state of Δl powder and PB coarse powder on which such an alumina sol coating layer is formed. As shown in the figure, a state was obtained in which coarse Pb powder with small particle size was uniformly dispersed and deposited on the surface of AI powder with large particle size via a coating layer of alumina sol. That is, uneven distribution of gravity due to the difference in specific gravity between AI and Pb did not occur, and the coarse Pb powder was evenly dispersed above and below.

Such A1. Pb powder mixture was heated at 150°C for about 2 hours.
The sample was heated to a temperature of 100 mL and dried in air. As a result, the coating layer of alumina sol gelled, and the bonding force between the AJ powder and the PB powder was further improved, and they did not separate again during the manufacturing process.

After that, the dried A1. A mold was filled with the Pb powder mixture, and sintering was performed at 500° C. for about 30 minutes. As a result, as shown in FIG. 1(B), an AJ-Pb alloy bearing material was obtained in which Pb was uniformly dispersed in AI as the base metal.

In addition, when an organic or inorganic binder such as sodium silicate was used in addition to alumina sol as the binder, an AJ-Pb alloy bearing material in which Pb was uniformly dispersed was obtained in the same manner as described above.

In addition, when A7 alloy is used as the base metal, or when using PB powder alone, Sn, Bi, or ln powder alone or two or more of these powders as the sliding component,
It was observed that these sliding components were uniformly dispersed.

Furthermore, even when the particle size was varied, it was found that the sliding component could be uniformly dispersed in substantially the same manner as described above.

(Conventional example) A powder similar to the above example (average particle size 40 um, 99
．． 7 wt% J611) and pb powder (average particle size 5 μm)
were mixed at a weight ratio of 85:15 without using a binder, and stirred for about 30 minutes.

FIG. 2(A) shows a mixed state of such AI powder and PB powder. As shown in the figure, the PB powder was unevenly distributed downward, resulting in a non-uniform dispersion of the lubricant component.

This is considered to be because the Pb powder fell during the mixing process due to the difference in weight between AJ and Pb and accumulated at the bottom.

When this AI and Pb alloy powder mixture was filled into a mold and sintered at 500°C for about 30 minutes in the same manner as in the previous example, as shown in Figure 2 (B), the base metal The result was an A-Pb alloy material with a non-uniform distribution in which a large amount of Pb was unevenly distributed under the AI.

〔Effect of the invention〕

As described above, according to the present invention, Sn, Pb, and Bi are added to the powder of AI or its alloy as the base metal and as lubricating components that are heavier than the base metal.

When manufacturing a sliding material by a sintering method by adding one or more types of In powder, uneven distribution of m-tiny components during powder mixing is prevented by forming a binder coating layer on the powder surface in advance. This has the effect that a sintered sliding material in which lubricating components are dispersed and mixed in a larger amount and more uniformly than in the past can be obtained in a state where the components can be freely controlled.

[Brief explanation of the drawing]

FIG. 1(A) is a schematic diagram showing a state of powder mixing in the middle of production according to an embodiment of the present invention, and FIG. 1(B) is a state of dispersion of RA lubricant components in the M rib material produced according to the above embodiment. FIG. 2(A) is a schematic diagram showing the state of powder mixing in the middle of production according to the conventional example, and FIG. 2(B) is a schematic diagram showing the state of the lubricant component fraction of the sliding material manufactured according to the conventional example. It is a diagram. (A) (B) Figure 1 (Al (81 Figure 2)

Claims (1)

[Claims] A powder of aluminum or its alloy and one or more powders selected from tin, lead, bismuth and indium are mixed and stirred with a binder made of an organic or inorganic material, and then sintered. A method of manufacturing a sliding material characterized by integrating the sliding material.