JPS6250445A - Fe-base sintered material for sliding member - Google Patents

Abstract

PURPOSE:To improve the wear resistance of an Fe-base sintered material and the lubricity at high temp. by impregnating a prescribed amount of Pb into the sintered material consisting of a dispersed phase forming component such as an Fe-Cr alloy and matrix forming components including Cu and Ni. CONSTITUTION:Pb is impregnated into a porous Fe-base sintered material consisting of, by weight, 1-15% dispersed phase forming component, 0.1-5% Cu, 0.1-5% Ni, 0.02-0.5% C and the balance Fe as matrix forming components by 5-30% of the amount of the sintered material to obtain an Fe-base sintered material for a sliding member. The dispersed phase forming component is an Fe-Cr alloy contg. 0.1-8% Mo and 40-70% Cr, an Fe-Mo alloy contg. 40-70% Mo or a mixture thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention provides excellent wear resistance, arc resistance, lubricity at high temperatures, and welding resistance9, as well as extremely low l
! This invention relates to a Fed sintered material that has JrM resistance and attack resistance and exhibits excellent performance when used as a sliding member that requires these characteristics, especially a sliding member such as a pantograph slider of an electric car. It is something.

[Conventional technology]

Conventionally, many Cu-based sintered materials and l''e-based sintered materials containing solid lubricants such as graphite and sulfide dispersed therein have been proposed and put into practical use as materials for sliding members.

All of these conventional materials for sliding members ensure excellent wear resistance due to the base material, and on the other hand, they contain solid r
88] The agent increases the lubricity with the mating material and suppresses the aggressiveness of the mating material.

[Problem that the invention seeks to solve]

However, in recent years, with the increase in speed and labor saving, the usage conditions for sliding members are becoming even more severe, but the conventional materials for sliding members mentioned above cannot adequately cope with this.
Therefore, there is currently a demand for the development of materials for sliding members having even better properties.

[Means for solving problems]

Therefore, from the above-mentioned viewpoint, the present invention is based on the results of research to develop materials with excellent properties required for sliding members. ), Mo: 0.1 to 8% as a dispersed phase forming component.

Fe-Cr alloy containing 40 to 70% Cr, and Mo
: 1 to 15% of one or two of the e-Mo alloys containing 40 to 70%.

Contains, and if necessary, Cr: 1-15%.

C1Cu:
o, 1-5%.

Ni: 0.1-5%.

C: 0.02 to 0.5%.

5 to a porous Fe-based sintered material having a composition containing Fe as a matrix-forming component and unavoidable impurities, at a ratio of 1 to this porous Fed sintered material.
The Fc-based sintered material impregnated with ~30% PB has excellent wear resistance, arc resistance, lubricity at high temperatures,
It has excellent adhesion resistance, extremely low frictional resistance, and resistance to attack by opponents. Therefore, it can be used as sliding members that require these characteristics, especially sliding members such as sliders for pantographs in electric cars. They found that it exhibits excellent performance in certain cases.

The present invention has been made based on the above findings, and the reason why the composition of the Fe-based sintered material is limited as described above will be explained below.

(a) Mo Mo acid component, which forms a dispersed phase and is easily oxidized in the air, forms molybdenum oxide due to the heat generated by sliding during practical use of the material, and the molybdenum oxide formed as a result is a metal Since it has the effect of suppressing adhesive wear due to contact between materials, the presence of this Mo acid component significantly improves the wear resistance and welding resistance of the material, but if the content is less than 0.1%, On the other hand, if the Mo content exceeds 8%, it will not bond firmly with the base material at a sintering temperature of 1300°C or lower, resulting in a decrease in the mechanical strength of the material. The content was determined to be 0.1 to 8% because the content would be too low to withstand practical use.

(b) Fe-Cr alloy and [e-Mo alloy These components both form a dispersed phase and have the effect of improving the wear resistance, arc resistance, and lubricity of the material at high temperatures. If the content is less than 1%, the desired effect will not be achieved, while if the content exceeds 15%, the mechanical strength of the material will decrease and it will not be able to withstand practical use. The content was determined to be 1 to 15%.

In addition, the content of Or and Mo in these alloys was limited to 40% to 70%, respectively, because the content was 40%.
Fe-Cr alloys and Fe-Mo alloys with a content of less than 70% cannot secure the desired properties, namely wear resistance, arc resistance, J3 and lubricity at high temperatures; Fe-Cr alloy and Fe-M
This is because the raw material powder for o alloy is difficult to manufacture.

(C) Cu The CLI component has the effect of not only solidly dissolving in the base material and strengthening it, but also improving the sinterability during material production and roughly improving the PB impregnation property. 0.1%
If the content is less than 5%, the desired effect cannot be obtained; on the other hand, if the content exceeds 5%, not only will the hardness of the substrate increase, but also the strength will decrease.
The content m was determined to be 0.1 to 5%.

(d) Ni The Ni component also acts as a solid solution in the base material, strengthens it, and improves the sinterability, similar to the Cu component, but if the content is less than 0.1%, the above effect is lost. On the other hand, if the content exceeds i)%, the hardness and electrical resistance of the material will increase, causing performance deterioration when used as a sliding member. Therefore, the content of M was determined to be 0.1 to 5%.

(e) C The C component, like the C0 and Ni components, has the effect of forming a solid solution in the base material, strengthening it, and stabilizing the sinterability, but its content m is less than 0.02%. On the other hand, if the content exceeds 0.5%, the hardness of the material will significantly increase, and the aggressiveness of the material will further increase, making the sliding member Therefore, the content was set at 0.02 to 0.5%.

cr Cr component is MoC component Fe-Cr alloy, and Fe-
Forms a dispersed phase together with Mo alloy, and especially in coexistence with the Fe-Cr alloy and Fe-Mo alloy, wear resistance,
Since it has the effect of further improving arc resistance and R8 lubricity at high temperatures, it is included as necessary when further improvement in these properties is required, but if the content is less than 1%, On the other hand, if the content exceeds 15%, the mechanical strength of the material decreases and becomes unusable in practical use, as in the case of Fe-Cr alloys and Fe-Mo alloys. Therefore, its content was determined to be 1 to 15%.

In addition, the Fe14 sintered material of the present invention can be manufactured by a normal powder metallurgy method, but in this case, if the Mo powder used as the raw material powder is made too coarse, Mo oxidation may progress during practical use. Since the desired effect cannot be achieved due to the delay, it is desirable that the particle size is fine, 100 mesh or less. In addition, in the case of Fe-Cr alloy powder, Fe-Mo alloy powder, and Cr powder, which are also used as raw material powder, the particle size is -20 m
The particle size is preferably within the range of 250 mesh to +250 mesh; this is because coarse particles exceeding 20 mesh are difficult to achieve uniform mixing;
This is because when the grains become finer than sh, the electrical resistance of the material increases and the mechanical strength decreases. Roughly the same 1: It is desirable that the C powder, Ni powder, CIJ powder, and C powder each have a mesh size of 100 mesh or less in order to ensure good sinterability.

Furthermore, the above [P immersed in the pores of the e-based sintered material 1]
Regarding impregnation b, if the amount of impregnation is less than 5% in proportion to the e-based sintered material, the desired low FJ abrasion resistance and opponent attack cannot be secured;
%, the density of the Fe-based sintered material decreases, which results in a decrease in arc resistance. It was set at 5-30%.

〔Example〕

Next, the FeJ3 sintered material of the present invention will be specifically explained using examples.

-60mesh to +150 each as raw material powder
MoC powder Fe-C with particle size within the range of meSh
r alloy (containing 60% Cr) powder, Fe-Mo alloy (M
o: 60% content) powder, Fe powder, Cu powder, Ni powder, C\iI powder, and Or powder are prepared, and after blending these raw material powders into the composition shown in Table 1, and combining them. In order to obtain different Pb impregnation m1, that is, various porosities, the powder was press-formed at a predetermined pressure within the range of 3-6 tons/ci, and this green compact was injected with decomposed ammonia gas. The present invention is produced by sintering in an atmosphere at a predetermined temperature within the range of 1150 to 1200°C for 60 minutes, and subsequently impregnating the sintered body with Pb as shown in Table 1. 1=28 Fe-based sintered materials were produced.

Next, the obtained F13 sintered material of the present invention 1 to 2
8, circling speed: 25-/hr, 50Km/hr.

100 touches/hr.

Sliding distance = 100 chants.

Pressing crab Ely.

Matching material: Hard copper.

Conducting a sliding test under the conditions of no current and 100V AC, 50A current, and measuring the specific wear and tear.
The amount of wear on hard copper, which is the mating material, was measured. The results of these measurements are shown in Table 2. Furthermore, for the purpose of comparison, Table 2 shows the sliding test results under the same conditions for Feu sintered materials that have been conventionally generally used as sliding members.

[Effect of the invention] From the results shown in Table 2, the Fe-based sintered materials 1 to 1 of the present invention
No. 28 is conventionally used as a sliding member because it has excellent wear resistance, arc resistance, lubricity at high temperatures, and welding resistance, as well as extremely low frictional resistance and attack resistance. It exhibits far better surrounding characteristics than conventional FC-based sintered materials, and these results indicate that it is particularly suitable for use in sliding members such as sliders for pantographs in electric cars. One thing is clear.

Claims (2)

[Claims] (1) Fe-Cr alloy containing Mo: 0.1-8%, Cr: 40-70%, and Mo
: 1 to 15% of one or two of the Fe-Mo alloys containing: 40 to 70%, and Cu:
0.1 to 5%, Ni: 0.1 to 5%, C: 0.02 to 0.5%, and the remainder consists of Fe as a base forming component and unavoidable impurities (more than ) is impregnated with Pb in an amount of 5 to 30% by weight relative to the porous Fe-based sintered material. (2) Fe-Cr alloy containing Mo: 0.1-8%, Cr: 40-70%, and Mo
Cr: 1-15%, Cu:
0.1 to 5%, Ni: 0.1 to 5%, C: 0.02 to 0.5%, and the remainder consists of Fe as a base forming component and unavoidable impurities (more than ) is impregnated with Pb in an amount of 5 to 30% by weight relative to the porous Fe-based sintered material.