JPS5884906A - Production of double layered sliding member - Google Patents

Abstract

PURPOSE:To produce a double layered sliding member easily by heating a steel plate or a cast iron plate and a metallic powder mixture for forming of a sintered alloy layer under static pressurizing thereby forming the sintered alloy layer and binding the sintered alloy metal to the steel plate or case iron plate integrally. CONSTITUTION:A steel plate or cast iron plate 23 to serve as a backing metal is placed on a bottom die 22 and a metallic powder mixture 24 for forming a sintered alloy is placed uniformly thereon to a desired thickness. A top die 21 is superposed thereon. While these are statically pressurized with an oil hydraulic press 27, both are heated in an induction heating furnace 25. Then the liquid phase metal in the mixture 24 melts and infilters among the solid phase metallic particles and between the backing metal 23 and the solid phase metallic particles, thereby forming a sintered alloy layer; at the same time, the sintered alloy layer is bound integrally with the metal 23 as well, whereby the double layered sliding member is obtained. The metallic powder mixture consists, by weight %, of 2-12 Sn, 4-20 Pb, <2 Ni, and the balance Cu, and contains >2 powder of Sn simple substance.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multilayer sliding part #O11 method that exhibits excellent lubricity and wear resistance under medium to high loads.

The sliding members used in piston pumps and vane pumps must have hardness and strength to withstand high impact loads, and are usually multi-layered sliding members reinforced with a backing metal. is used.

The performance of such a multilayer sliding member is highly dependent on the thickness and hardness of the backing metal.

Conventionally, in order to obtain this type of multilayer member, a metal powder mixture for the sintered alloy layer is placed on a thin steel plate, and then heated, pressed, and rolled to form a sintered alloy layer on the steel plate. A gold layer is formed, and the sintered alloy layer is integrally bonded to a steel plate to form a multilayer member with a thickness of several meters (in most cases, less than J meters).
A method of joining the multi-layered members using a separately prepared thick backing steel filler material is used, and attached FIG. 7 shows a cross-sectional view of an example of a multi-layered sliding member manufactured by such a conventional method. / is a sintered alloy layer, λ is a thin steel plate covered with a sintered alloy layer 1, 3 is a brazing filler metal, and 3 is a back metal steel plate.

The nine multi-layer oscillations are manufactured using conventional methods, and their brazing is sometimes subject to high-level rounding, and the sintered metal layer and the back metal steel plate are both subject to deterioration and sliding. Characteristics, impact resistance characteristics and impact resistance 4! ! There was a drawback that the performance required for a sliding member was inferior.

, Suitable for mass production, but in the case of multi-layer sliding members with thick back metals, the demand is relatively small. In the past, products became expensive and it was difficult to meet the 91st problem.The above-mentioned Utsushima Norihiro used Okashima material with hardness and strength for the backing metal, but in other words, only a backing metal with relatively low hardness IIO could be used, so the impact load Our only challenge is to obtain a sliding member that can withstand medium to high loads.

This invention is ll! This invention provides an improved method for manufacturing multi-layer sliding members.

That is, in the manufacturing method of the multilayer sliding member of the present invention, a steel plate or cast iron plate and a metal powder mixture for forming a sintered alloy are heated under pressure to form a sintered alloy layer, and at the same time, The method is characterized in that the sintered alloy layer is integrally bonded to the steel plate or cast iron plate.

When using the manufacturing method of the present invention, a multilayer sliding member having a reinforcing steel backing plate or cast iron plate can be easily manufactured without using the brazing process as in conventional methods. . In addition, the resulting multi-layer sliding member is strongly bonded to the backing metal, so it can withstand high loads during impact loads, and since brazing is not exposed to high temperatures as in conventional methods, sintered bonding is possible. Neither the gold layer nor the backing metal undergoes deterioration and deformation, resulting in excellent sliding properties.

The attached FIG. 2 is a cross-sectional view of a multilayer sliding member obtained by the manufacturing method of the present invention, where // is a sintered alloy layer, and 7.2 is a back metal φ steel plate or cast iron plate. .

Attached! ! Figure 3 L1 is a partially cutaway diagram showing the state in which a multi-layer sliding member is manufactured according to the manufacturing method of the present invention. An example of a refreshing embodiment for manufacturing a multilayer member according to the present invention will be explained according to FIG.

First, a steel plate or cast iron plate 3 serving as a back metal is placed on the lower metal lid 2λ, and a metal powder mixture 244 for forming a sintered alloy layer is applied to the steel plate or cast iron plate λ3 to a desired uniform thickness. The upper mold was placed on top of the upper mold, and heated in an induction heating furnace while applying static pressure using a hydraulic press 7.

Then, the liquid phase metal in the metal powder mixture is melted by heating and penetrates into the spaces between the same phase metal particles and between the backing metal 23 and the solid phase metal particles, filling those spaces, and the liquid phase metal and the same phase metal An alloy is formed by interdiffusion between the particles, the backing metal and ogKTh, and a sintered alloy layer is formed.At the same time, the sintered alloy layer is joined to the backing metal 4 in one direction to form the desired multilayer sliding member. can get.

Although induction heating is used in the nine examples shown in FIG. 3, the heating does not necessarily have to be induction heating, and other heating means such as a gas burner may be used. The heating temperature should be at least the melting point of the liquid metal in the metal powder mixture, but in order to promote the densification of the sintered alloy layer and increase the bonding strength with the backing metal, the heating temperature should be lower than the melting point of the liquid metal. It is desirable to set the temperature to a high temperature. However, the heating temperature must be below the melting point of the alloy formed by the metal in the same phase and the metal in the liquid phase. Must not be at high temperatures.

The pressure is continuously applied at such a strength that the metal powder mixture is always in close contact with the upper mold during the sintering process. Such pressurization promotes the flow of the liquid metal and helps prevent the pores from becoming coarse during solid phase sintering. It is also desirable to increase the pressure when the melting point of the liquid metal is reached and immediately before the end of sintering. By increasing the pressure, the above-mentioned pressurizing effect can be further ensured.

As the metal powder mixture for forming the sintered alloy layer according to the present invention, for example, a lead bronze metal powder mixture, an aluminum bronze metal powder mixture, a phosphor bronze metal powder mixture, etc. can be used, and particularly preferred metals are The powder mixture is a lead bronze based metal powder mixture.

As a representative example of the metal powder mixture for forming the sintered alloy layer in the present invention, a case where a lead bronze metal powder mixture is used will be described in detail below.

A preferred lead bronze metal powder mixture for use in the present invention is a metal with a component ratio of Kame no Sha, Tin - ~ / Ko weight round, lead part - Ko weight 9, Nirakeruko weight 9 or less, and the balance consisting of copper. It is a powder mixture. It is necessary to use at least λ weight 9 of the tin as a single tin powder, and the remaining tin component may be used as a single tin powder, or as an alloy powder with other metals. It may also be used. Other metal components other than the tin plate may be used as a single metal powder or as a copper alloy powder.

If the present invention is carried out using such a bronze-based metal powder mixture, during sintering by pressurizing and heating in step 7, the simple tin powder will first be melted in a bath and become a liquid phase. The metal powders penetrate into the pores of each other and form an alloy by mutual diffusion with these other metal powders, and are sintered. At the same time, the tin liquid also infiltrates between the other solid phase metal powder and the backing metal to form an alloy in the same way, thereby firmly bonding the backing metal and the sintered alloy layer together. In order to fully exhibit the action of tin as a liquid phase metal, it is necessary to use tin as a single powder in a proportion of 2 by weight or more in the bronze-based metal powder mixture. Tin also serves as a bronze-forming component, increases the strength of the base of the sintered alloy layer, and contributes to improved wear resistance. However, if the tin component exceeds 72% by weight and 96% gold, the sintered alloy layer becomes hard and brittle, making it unsuitable for use as a material for sliding parts. For this purpose, tin is used in the bronze-based metal powder mixture in the range λ to 7.2 times 9.

Lead is independently dispersed in the bronze-based sintered alloy layer and contributes to improving the lubricity of the sliding member and the compatibility with the mating material. If the proportion of lead is less than 9% by weight, it will not be able to fully exhibit its effects, and if the proportion of lead exceeds 9% by weight, the pressure resistance of the sliding member will decrease. For this purpose, the lead component should be within the range of μ to −0 weight 9.

It diffuses into the steel, increasing the strength of the bronze-based sintered alloy layer, contributing to improved cavitation resistance and mechanical strength.

Steel is mixed with the mixed powder for forming the sintered alloy layer as an alloy powder or single powder, and both are alloyed with tin by pressure and heating to form bronze, which improves the strength of the sintered alloy layer. and contributes to improved wear resistance.

In carrying out the present invention using a 'W sea bream metal powder mixture containing tin as the liquid phase metal, the purpose can be achieved as long as the heating temperature is 2°C or higher; In order to form a bonded gold layer, it is desirable to heat to 610 to 700 U. However, when heated to a high temperature above rooc,
Such high temperature heating should be avoided since the sintered alloy layer will partially melt and cause linear shrinkage. ti, the pressurization in that case is usually O0/~0. , about 2 MPa, but it is desirable to temporarily increase the pressure by 7j to JOMPaK when the tin powder melts and immediately before the end of sintering.

When using a bronze-based metal powder mixture as the metal powder mixture for forming the sintered metal layer in the present invention, if the steel plate or cast iron plate serving as the backing metal is plated with copper in advance, the backing metal and the sintered metal layer This is preferred because it can be easily and firmly bonded to the In that case, the thickness of copper plating is usually 3~/j
A thickness of about μ is sufficient, and any other plating method such as electroplating can be used for copper plating.

Next, the present invention will be explained in further detail with reference to Examples.

Example 1 Diameter/λmm, thickness ″5 using JIS a reference IC steel material
A disk was prepared, and one side of it was plated with copper to a thickness of IC according to a conventional method. Using the same equipment as shown above, the large disk 23 was placed on the bottom metal Wn with the plating side facing up. Next, to the disk λJJ: parts by weight of tin powder, parts by weight of lead powder,
A metal powder consisting of 3 parts by weight of nickel powder, 3 parts by weight of copper powder, and 10 parts by weight of lead bronze powder consisting of 9 parts by weight of tin powder, 9 parts by weight of lead/copper, and 74 parts by weight of copper. , Yuj
The upper mold 2/ is placed on top of it, and the entire metal is heated in an induction heating furnace and continuously applied with a pressure of Q/MPa by a hydraulic press J7. When the tin powder starts to melt and reaches λ4Iθ~260CIIC, increase the JOMPak pressure for j seconds and further increase the JOMPak pressure to 1IC4JOCK.
When the temperature is different, increase the JOMPaK pressure again for 10 seconds. After increasing the final pressure, immediately stop heating (3 minutes after the start of heating), cool to room temperature, and then remove the molded product from the mold.
When I started out, it was 8! JC steel back metal, tin 10 weight 119
6. The sintered alloy layer consisting of lead IO weight 9, nickel/jim 96, and the remainder copper was firmly bonded to obtain a 9 multilayer sliding member.

This multi-layer sliding member is made of /Q mt'1k, diameter l
Processed into a pulp plate of λQ mm and attached to a piston pump, pressure ≠〇 MPa % rotation speed / 1100
After 300 hours of continuous operation at RP-, the amount of wear on the sliding members was extremely small, and no cavitation or erosion was observed.

Example λ JIS Fezs material was used, diameter/47 mm,
Comes with a 27mm thick port! ! A cast iron disk was cast, and one side of the plate was plated with copper to a thickness of 10μ in accordance with a conventional method. Hereinafter, in the same manner as in Example/, parts by weight of tin powder, parts by weight of lead powder, parts by weight of nickel powder/Ik,
A mixed metal powder consisting of 37 parts by weight of copper powder and 30 parts by weight of lead bronze powder consisting of 1 part by weight of tin, 1 part by weight of lead/4' by weight and 71 parts by weight of pot was placed on a uniform thickness of 1 tNm. When sintered by heating and pressurizing, the result is a multi-layer sliding structure in which a sintered alloy layer consisting of 1 weight of tin, 9 weight of lead/j, 7 weight of nickel, and the balance copper is firmly bonded to the cast iron plate back metal. A member was obtained.

Thickness, lQmm, diameter / 4011
Processed into 1111 pulp plate, page pump K1
11th place, pressure MPa, rotation speed 3200 yap・m.
When the vane was operated continuously for 00 hours, the compatibility with the vane was poor, and there was very little wear.

[Brief explanation of drawings]

FIG. 7 is a cross-sectional view showing an example of a multi-layer sliding member manufactured by a conventional method, FIG. 2 is a cross-sectional view showing an example of a multi-layer sliding member obtained by the manufacturing method of the present invention, and FIG. FIG. 2 is a partially cutaway front view showing a state in which a multilayer sliding member is manufactured according to the method of the present invention. Each symbol in the middle indicates the following. / see Sintered alloy layer - Thin steel plate 3... Brazing metal backing metal layer 1 Back metal steel plate //--- Sintered alloy layer 12・e・ Backing metal steel plate Makasha cast iron plate... Upper mold here・-- Lower mold 3 @ fist Steel plate or cast iron plate 11 Metal powder mixture 3 ... Induction heating furnace 6 fist Coil core for induction heating e Hydraulic press

Claims (1)

[Claims] t. A steel plate or a cast iron plate and a metal powder metallurgy for forming a sintered metal layer are heated under quiet pressure to form a sintered metal layer, and at the same time, the isthmus metal layer is heated to form a sintered metal layer. A method for manufacturing a multi-layer sliding member, characterized by integrally joining it to a steel plate or cast iron plate. (Y) The steel plate or cast iron plate is a steel plate or cast iron plate with steel plating, and the metal powder mixture for forming the sintered alloy layer has a total component ratio of tin ~ l - weight 9, lead ginseng ~, 20 8. The method according to claim 7, wherein the metal powder alloy is made of 9% by weight, nickel by 9% by weight or less, and the balance is copper, and contains at least 2% by weight as a single tin powder.