JPH02118002A - Sintered laminating body for copper alloy powder sheet - Google Patents

Abstract

PURPOSE:To improve slidability and wear resistance of a sintered laminating body by kneading the specific compositions of Cu-Sn (Zn) series raw material powder and synthetic resin binder, sticking a sheet obtd. by rolling on a base material and sintering. CONSTITUTION:The sheet is manufactured by kneading 85-97wt.% the raw material powder composed of at least one kind of 5-15% Sn and 10-43% Zn, 1-10% Pb, at least one kind of 0.5-10% Fe and Ni and balance of Cu, and 3-15% the synthetic resin binder and rolling. This sheet is stuck to the base material of piston shoe for hydraulic pump, etc., as a sliding material and jointed with the sintering to make the laminated body. In the above Cu alloy raw material powder, if necessary, at least one kind among Ti, Si, Mn and Al, boride of Mo2B, Zr2B, TiB2, etc., oxide of Al2O3, mullite, etc., nitride of TiN, Si3N4, etc., are contained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a laminate in which a copper alloy powder sheet having excellent sliding properties and wear resistance is sintered and bonded to a base material using a powder metallurgy method.

(Prior art) Conventionally, this type of alloy powder has been produced by depositing an alloy powder sheet using a Ni-based or Go-based self-fusing alloy powder and a retractable acrylic resin on a metal base material with a solvent such as toluene. It is known that the adhesive is applied after being moistened and then heated and fused in the atmosphere.

(For example, see Japanese Patent Application Laid-open No. 51-838343.) With such an alloy powder sheet, an alloy layer can be formed relatively easily on the surface of the base material.

(Problem to be Solved by the Invention) However, when heating and sintering such an alloy powder sheet, the synthetic resin is burned out at a temperature of 200 to 300°C and adhesiveness is lost, so the base material is flat. It was applicable only to the upper surface, and could not form an alloy layer on sloped surfaces, curved surfaces, or even the lower surface due to slipping or falling.

Therefore, although Cu-3n-based, Cu-Zn-based, and powder sheets have been used as bearing materials, they have been produced as a single product and press-fitted, and the shape has been limited to cylindrical ones. In order to form an alloy layer on a product with a complex shape, it is manufactured by processing after casting by brazing, thermal spraying, or casting, but the manufacturing cost is high6.The present invention aims to solve this problem by using copper. A sintered laminate of alloy powder sheets is provided.

(Means for solving the problem) In order to achieve the above object, in the present invention, Sn: 5 to
15 Wt% or at least one of Zn: 10-43 Wt% and Pb: 1-10 Wt%, P: 0.05-1
．． 5 W t%, at least one of Fe and Ni is 0
．． 5 to 10 Wt%, Cu: distribution composition consisting of the remainder 85 to 97 Wt% of raw material powder and 3 to 15 W of synthetic resin binder
A sheet obtained by kneading and rolling t% is adhered to a base material and joined by sintering. In addition, Ti, S
at least one of i, Mn, AI and MoJ, ZrJ
, TiBg boride, Afzos, mullite oxide, SiC, TiC, ZrC, TaC1WC carbide, TiN, 5iJa nitride, and a composite carbonitride of these.

Furthermore, an appropriate amount of fibers or meshes of at least one of metal, carbon, and synthetic resin is added to these raw material powders.

(Function) The sintered laminate of the first invention uses copper alloy powder and a synthetic resin binder to ensure adhesion between the copper alloy powder sheet and the base material during sintering from room temperature to 900°C. knead,
The rolled sheet is attached to the base material. In addition, by adding P as a Fe-P alloy (P: 27 to 30 Wt%) powder, we can remove the oxide film on the surface of the base material to be joined during sintering and keep it clean, and also remove Fe (including P). Cu-
3n, creates a Z phase region of Cu-Zn and improves bonding strength.

(See Fig. 5) Furthermore, even when sintered in a high temperature range, abnormal expansion peculiar to copper alloy powder materials can be prevented, and high-density sintering (porosity of 10% or less) can be achieved.

On the other hand, by adding Pb to copper alloy powder, 5n-
A low melting point Pb solder is produced to improve wettability with the base material, thereby improving adhesion at low temperatures and bonding strength during sintering. (See FIG. 5) Furthermore, Pb improves the sliding properties and seizure resistance of the sintered laminate.

Next, in the present invention, the content of each component! (hereinafter weight%
We will explain the reason why we limited the following.

(a) Sn content If the Sn content in the copper alloy powder is less than 5%, the evaporation of Pb cannot be suppressed and it is difficult to sinter at high density. The Sn content was determined to be 5 to 15% since the shape property was decreased.

(b) Zn content Zn determines the base composition of the copper alloy and needs to be α+β type or β type in order to ensure toughness. If the Zn content is less than 10%, the α phase will increase and the β phase will decrease, making it impossible to secure the desired wear resistance. On the other hand, if it exceeds 43%, the α phase will precipitate and the strength will decrease. Therefore, the Zn content was determined to be 10 to 43%.

(c) Pb content If the Pb content is less than 1.0%, the effect of improving wettability with Fe is insufficient and galling due to hard phosphide particles during sliding cannot be prevented. The Pb content was determined to be 1.0 to 10.0% since the strength of the sintered body would drop below the practical strength of 20 kg/mm'' if the Pb content was exceeded.

(d) P content If the P content is less than 0.05%, the bonding strength with the base material cannot be maintained or the blistering of the sintered body cannot be prevented. If it exceeds this, the elongation of the sintered body becomes 3% or less, and the seizure resistance during sliding also decreases, so the P content was set at 0.05 to 3.5%.

Further, 85 to 97% of the copper alloy powder and 3 to 15% of the synthetic resin binder are kneaded and rolled to form a copper alloy powder sheet and adhered to a base material. Here, the reason for limiting the type and amount of synthetic resin will be explained.

(e) Type of synthetic resin In order to form a good alloy layer on a base material by directly sintering a copper alloy powder sheet, the following conditions must be satisfied.

(a) It has adhesive properties at room temperature and is flexible as a sheet.

(b) Due to thermal decomposition, gas generation is small, there is no foaming deformation, and the amount of residual material is small.

(c) The required shape can be maintained without peeling from the base material during temperature rise.

The only resin that satisfies these conditions is acrylic resin, which decomposes at 250°C, does not cause carbonization, and has considerable adhesiveness. As the temperature rises further, carbonization progresses, but phenomena such as blistering due to gas generation do not occur, and even at temperatures of 600°C or higher, separation from the base material does not occur.

On the other hand, thermosetting resins such as acrylic melamine resin, alkyd melamine resin, vinyl acetate resin, and two-component curing type (isocyanate curing type) resin all foam, and polyvinyl alcohol has problems in shape retention.

(r) Distribution amount of synthetic resin There are two methods for forming copper alloy powder into sheets:

(a) After kneading acrylic resin and copper alloy powder diluted with solvents such as acetone, toluene, and M-E-K (methyl ethyl ketone) to form a slurry, pour it onto a mold covered with release paper. After evaporating the solvent, it is passed through rolling rolls to form a sheet.

(b) A binder is prepared by mixing a tetrafluorinated ethylene resin emulsion and an acrylic resin emulsion at a ratio of 1:1.

After thoroughly kneading this and copper alloy powder with a kneader, 1
The water in the binder is evaporated by heating to 00 to 150°C. Further, this kneaded product is heated to 80 to 100°C and passed through a rolling roll to form a sheet. If the blending amount of the acrylic resin used as a binder is less than 3%, the adhesiveness will be insufficient and the sheet will become brittle, making it difficult to secure the necessary flexibility of the sheet. The amount of acrylic resin blended was determined to be 3 to 15% because the resin content would be excessive, adversely affecting the porosity and making it impossible to bond to the base material.

Further, the second invention includes Ti, Si, Mn,
At least one AfL and other borides, oxides,
Addition of carbides, nitrides, etc. improves the wear resistance and mechanical strength of the sintered laminate. Furthermore, the third invention further improves the properties of the sintered laminate by adding metal, carbon, synthetic resin fibers, etc. to these raw material powders.

(Example) Hereinafter, the sintered laminate of the present invention will be described by way of example with reference to the drawings.

Embodiment 1 FIG. 1 is a sectional view of Embodiment 1 in which a sliding material 2 is bonded and sintered to a bonded portion 3 of a base material 1 of a piston shoe for a hydraulic pump. As the sliding material 2, 11% Sn with a particle size of 200 mesh or less, 3% Pb with a particle size of 200 mesh or less, and 3% Pb with a particle size of 3
Phosphorous iron powder CP of 50 mesh or less: 3% (contains 21%)
p: o, a%), electrolytic copper powder with a particle size of 200 mesh or less 8
After adding 3% of kerosene and 0.1% of kerosene, they were mixed uniformly, put into 7% of acrylic resin diluted with acetone, kneaded, and made into a slurry, which was then poured onto release paper and made into a sheet.

This was pasted on the joining part 3 of the copper base material 1 of SCM440H (Cr 1%, Mo 0.3%), and after sintering and joining at a heating rate of 15°C/min and a temperature of 900''C in an AX gas atmosphere,
It was processed into the shape of a piston shell. Table 1 shows the joint strength, tensile strength, and wear amount of the sliding material at this time.

It shows superior sliding characteristics compared to the comparative material PC31C (high strength brass). In addition, the 500H durability test was conducted under constant torque load with 150H1 swash plate switching and 150H1 pressure switching.
50H1 A test was conducted by combining four types of 50H patterns with a constant pressure capacity.

Table 1, Example 2, Figure 2 shows the spherical joint 6 of the base material 4 of the cylinder block.
FIG. 3 is a cross-sectional view of Example 2 in which a sliding material 5 is bonded and sintered. As the sliding material 5, 11 pieces of Sn with a particle size of 200 mesh or less are used.
%, 10% Pb with particle size of 200 mesh or less, particle size of 35
1.5% of phosphorous iron powder (P: 27% content) below 0 menoshie
(P: 0.4%), electrolytic copper powder with a particle size of 200 mS or less was used as the balance, and after adding 0.1% of kerosene, it was mixed evenly, and to this, 1% of a tetrafluoroethylene resin emulsion and an acrylic resin emulsion were added. Add 7% of synthetic resin binder made by mixing 1:1 and thoroughly knead with a kneader.
This was heated to 100-150°C to evaporate the water in the synthetic resin binder, and then the mixture was heated to 80-150°C.
It is heated to 0°C and rolled into a sheet, which is then SC
Pasted on the curved sliding part 6 of the M440H steel base material 4, heated at 7++ in an AX gas atmosphere at a thermal rate of 15°C/min and a temperature of 870°C.
After sintering and joining, it was processed into the shape of a cylinder block. Table 1 shows the joint strength, tensile strength, and amount of wear of the sliding material at this time. It shows superior sliding properties compared to the comparative material LBC (lead poison fly).

Figures 3 and 4 are photographs of the metal structure near the joint 3 in the first embodiment, showing the P distribution and Fe distribution at the joint interface, respectively.
A two-phase region is formed in which the phases crystallize. Since the bonding interface has an uneven shape in this way, the bonding strength is improved.

In these examples, Cu-3n based sintered material was explained, but C
Similar results can be obtained with u-Zn-based and other copper alloy sintered materials.

(Effects of the Invention) As explained above, according to the present invention, the following effects are achieved. There are many parts, including hydraulic parts such as cylinder blocks and valve plates, in which copper-based sliding materials are bonded to steel, but the formation of an alloy layer with strong bonding properties according to the present invention reduces the manufacturing costs of these parts. is significantly reduced.

It is used under high surface pressure because it prevents the abnormal expansion and blistering characteristic of sintered copper alloy materials and can be sintered to a higher density. We can provide sliding materials and wear-resistant materials at low cost.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the embodiment of the present invention, and FIG. 2 is the same
The cross-sectional view of Example 2, FIGS. 3 and 4 are metal structure photographs in place of the drawings of the joint in Example 1 of the present invention,
FIG. 5 shows the bonding strength of the sintered laminate of the present invention. l, 4... Base material 2.5... Sliding material (copper alloy powder sheet) 3.6...
joint

Claims (3)

[Claims] (1) Sn: 5 to 15 Wt% or Zn: 10 to 43
At least one type of Wt% and Pb: 1 to 10 Wt%, P:
0.05-1.5 Wt%, 0.5-10 Wt% of at least one of Fe and Ni, Cu: 85-97% Wt% of raw material powder and 3-3 Wt% of a synthetic resin binder.
15 Wt% was kneaded and the rolled sheet was attached to the base material,
A sintered laminate of copper alloy powder sheets that is bonded together by sintering. (2) The raw material powder according to claim 1 includes Ti, Si, Mn,
At least one of Al and Mo_2B, Zr_2B, T
i8_2 boride, Al_2O_3, mullite oxide, SiC, TiC, ZrC, TaC, WC carbide, T
A sintered laminate of copper alloy powder sheets, characterized in that it is made by adding nitrides of iN, Si_3N_4, and at least one of these composite carbons and nitrides. (3) A sintered laminate of copper alloy powder sheets, characterized in that the raw material powder according to claim 1 or 2 is added with fibers or meshes of at least one of metal, carbon, and synthetic resin.