Sliding bearing copper-based alloy material and preparation method thereof

Abstract

The invention provides a sliding bearing copper-based alloy material and a preparation method thereof, and belongs to the technical field of alloy materials. The sliding bearing copper-based alloy material provided by the invention is prepared from the following raw materials in percentage by mass: 5-8% of Ni; 2.5%-3.5% of Sn; 2-3% of Zn; 1.5 to 2.5 percent of Cr; 1.2 to 1.8% of Mg; 0.6%-0.9% of Zr; 0.1 to 0.4 percent of rare earth; 1-2% of graphite; 1%-2% of FeS; and the balance Cu. The sliding bearing copper-based alloy material provided by the invention does not contain lead, is green and environment-friendly, and has excellent antifriction and antiwear properties and mechanical properties.

Description

Technical Field

[0001] The invention relates to the technical field of alloy materials, and in particular to a sliding bearing copper-based alloy material and a preparation method thereof. Background Art

[0002] Sliding bearings are one of the key parts in the engine. The performance of sliding bearing materials has a direct impact on the performance of the engine. Copper-based alloy materials have good thermal conductivity and load-bearing capacity and are widely used in the preparation of sliding bearings. Lead is soft and has a low melting point. As a lubricant, it has good friction reduction and anti-wear properties in copper-based alloy materials for sliding bearings. However, lead is a heavy metal pollutant that can cause serious harm to human health and the ecological environment. Summary of the invention

[0003] The object of the present invention is to provide a sliding bearing copper-based alloy material and a preparation method thereof. The sliding bearing copper-based alloy material provided by the present invention does not contain lead, is green and environmentally friendly, and has excellent friction reduction and anti-wear properties and mechanical properties.

[0004] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0005] The present invention provides a sliding bearing copper-based alloy material, which is prepared from the following raw materials by mass content:

[0006] Ni 5~8%; Sn 2.5~3.5%; Zn 2~3%; Cr 1.5~2.5%; Mg 1.2~1.8%; Zr 0.6~0.9%; rare earth 0.1~0.4%; graphite 1~2%; FeS1~2%; and the balance Cu.

[0007] Preferably, the sliding bearing copper-based alloy material is prepared from raw materials with the following mass contents:

[0008] Ni 6~7%; Sn 2.8~3.2%; Zn 2.3~2.7%; Cr 1.8~2.2%; Mg 1.4~1.6%; Zr0.7~0.8%; rare earth 0.2~0.3%; graphite 1.3~1.7%; FeS1.3~1.7%; and the balance Cu.

[0009] Preferably, the rare earth includes La and / or Ce.

[0010] Preferably, the rare earths are La and Ce, and the mass ratio of La to Ce is 1:0.5-2.

[0011] The present invention provides a method for preparing the copper-based alloy material of a sliding bearing described in the above technical solution, comprising the following steps:

[0012] Mixing various raw materials for preparing the copper-based alloy material for sliding bearings, performing wet ball milling, and then drying to obtain ball milled material;

[0013] Pressing the ball-milled material to obtain a green body;

[0014] The green compact is sintered in a protective atmosphere to obtain the sliding bearing copper-based alloy material.

[0015] Preferably, the ball-to-material ratio of the wet ball milling is 5 to 10:1, the rotation speed is 200 to 300 rpm, and the time is 2 to 10 hours.

[0016] Preferably, the dispersant used in the wet ball milling includes one or more of water, ethanol and acetone.

[0017] Preferably, the pressing pressure is 300-500 MPa.

[0018] Preferably, the sintering includes a first sintering and a second sintering in sequence; the temperature of the first sintering is 800-850°C, and the holding time is 30-60 minutes; the temperature of the second sintering is 900-1000°C, and the holding time is 30-60 minutes.

[0019] Preferably, the sintering is carried out in a protective atmosphere; the heating rate from room temperature to the first sintering temperature is 7-10°C / min, and the heating rate from the first sintering temperature to the second sintering temperature is 3-5°C / min.

[0020] The present invention provides a sliding bearing copper-based alloy material, which is prepared from the following raw materials by mass content: Ni 5-8%; Sn 2.5-3.5%; Zn 2-3%; Cr 1.5-2.5%; Mg 1.2-1.8%; Zr 0.6-0.9%; rare earth 0.1-0.4%; graphite 1-2%; FeS 1-2%; and the balance Cu. The sliding bearing copper-based alloy material provided by the present invention does not contain lead, is green and environmentally friendly, and a small amount of graphite and a small amount of FeS are compounded and used as solid lubricants, so that the sliding bearing copper-based alloy material has excellent anti-friction and anti-wear properties; at the same time, the content of Ni, Sn, Zn, Cr, Mg, Zr and rare earth is strictly controlled, so that the sliding bearing copper-based alloy material has excellent mechanical properties (such as hardness and strength), in addition, Ni, Cr and rare earth are also beneficial to improving the heat resistance of the sliding bearing copper-based alloy material, and Zn is also beneficial to promoting the uniform distribution of the solid lubricant, ensuring that it fully exerts its anti-friction and anti-wear effects. The results of the embodiment show that the hardness of the copper-based alloy material of the sliding bearing of the present invention is 122-125 HB, the tensile strength is 588-593 MPa, and the radial crushing strength is 402-410 MPa; the friction coefficient is 0.08-0.20 at a test temperature of 400°C, and the volume wear rate is 1.08-2.11×10 -4 mm 3 ·N -1 ·m -1 . DETAILED DESCRIPTION

[0021] The present invention provides a sliding bearing copper-based alloy material, which is prepared from the following raw materials by mass content:

[0022] Ni 5~8%; Sn 2.5~3.5%; Zn 2~3%; Cr 1.5~2.5%; Mg 1.2~1.8%; Zr 0.6~0.9%; rare earth 0.1~0.4%; graphite 1~2%; FeS1~2%; and the balance Cu.

[0023] In the present invention, unless otherwise specified, the raw materials used are commercially available products well known to those skilled in the art or are prepared by methods well known to those skilled in the art.

[0024] In the present invention, the raw material for preparing the sliding bearing copper-based alloy material includes Ni 5-8% by mass, specifically 5%, 5.5%, 6%, 6.5%, 7%, 7.5% or 8%. The present invention controls the amount of Ni within the above range, which is conducive to making the sliding bearing copper-based alloy material have excellent mechanical properties and heat resistance.

[0025] In the present invention, the raw material for preparing the sliding bearing copper-based alloy material includes Sn 2.5-3.5% by mass content, specifically 2.5%, 2.6%, 2.7%, 2.8%, 2.9%, 3%, 3.1%, 3.2%, 3.3%, 3.4% or 3.5%. The present invention controls the amount of Sn within the above range, which is conducive to ensuring that the sliding bearing copper-based alloy material has excellent mechanical properties.

[0026] In the present invention, the raw material for preparing the sliding bearing copper-based alloy material includes Zn 2-3% by mass content, specifically 2%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9% or 3%. The present invention controls the amount of Zn within the above range, which is conducive to ensuring that the sliding bearing copper-based alloy material has excellent mechanical properties, and is conducive to promoting the uniform distribution of solid lubricants, ensuring that they fully exert their anti-friction and anti-wear effects.

[0027] In the present invention, the raw material for preparing the sliding bearing copper-based alloy material includes Cr 1.5-2.5% by mass content, specifically 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, 2.1%, 2.2%, 2.3%, 2.4% or 2.5%. The present invention controls the amount of Cr within the above range, which is conducive to making the sliding bearing copper-based alloy material have excellent mechanical properties and heat resistance.

[0028] In the present invention, the raw material for preparing the sliding bearing copper-based alloy material includes Mg 1.2-1.8% by mass, specifically 1.2%, 1.3%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7% or 1.8%. The present invention controls the amount of Mg within the above range, which is conducive to ensuring that the sliding bearing copper-based alloy material has excellent mechanical properties.

[0029] In the present invention, the raw material for preparing the sliding bearing copper-based alloy material includes Zr 0.6-0.9% by mass, specifically 0.6%, 0.7%, 0.8% or 0.9%. The present invention controls the amount of Zr within the above range, which is conducive to ensuring that the sliding bearing copper-based alloy material has excellent mechanical properties.

[0030] In the present invention, the raw material for preparing the sliding bearing copper-based alloy material includes 0.1-0.4% rare earth by mass content, specifically 0.1%, 0.2%, 0.3% or 0.4%. As an embodiment of the present invention, the rare earth includes La and / or Ce, specifically La and Ce, and the mass ratio of La to Ce can be 1:0.5-2, specifically 1:0.5, 1:1, 1:1.5 or 1:2. The present invention controls the amount of rare earth within the above range, which is conducive to making the sliding bearing copper-based alloy material have excellent mechanical properties and heat resistance.

[0031] In the present invention, the raw material for preparing the sliding bearing copper-based alloy material includes 1-2% graphite by mass content, specifically 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9% or 2.0%. As an embodiment of the present invention, the graphite can specifically be flaky graphite. The present invention controls the amount of graphite within the above range, which is conducive to making the sliding bearing copper-based alloy material have excellent friction reduction and wear resistance and mechanical properties.

[0032] In the present invention, the raw material for preparing the sliding bearing copper-based alloy material includes FeS1-2% by mass content, specifically 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9% or 2.0%. The present invention controls the amount of FeS within the above range, which is conducive to making the sliding bearing copper-based alloy material have excellent friction reduction and wear resistance and mechanical properties.

[0033] In the present invention, the raw material for preparing the sliding bearing copper-based alloy material includes a remainder of Cu, calculated by mass content.

[0034] As an embodiment of the present invention, the raw material for preparing the copper-based alloy material of the sliding bearing can be in powder form, wherein the particle size of graphite can be 5-10 μm; the particle size of FeS can be 50-80 μm, and the particle size of other raw materials can be independently 30-100 μm.

[0035] The present invention provides a method for preparing the copper-based alloy material of a sliding bearing described in the above technical solution, comprising the following steps:

[0036] Mixing various raw materials for preparing the copper-based alloy material for sliding bearings, performing wet ball milling, and then drying to obtain ball milled material;

[0037] Pressing the ball-milled material to obtain a green body;

[0038] The green compact is sintered in a protective atmosphere to obtain the sliding bearing copper-based alloy material.

[0039] The present invention mixes various raw materials for preparing the sliding bearing copper-based alloy material and performs wet ball milling to obtain ball milled material. As an embodiment of the present invention, the dispersant used in the wet ball milling includes one or more of water, ethanol and acetone, specifically water, ethanol or acetone. The present invention has no special limitation on the amount of the dispersant, as long as the wet ball milling is carried out smoothly; the ball-to-material ratio of the wet ball milling can be 5-10:1, and further can be 6-8:1; the rotation speed can be 200-300rpm, specifically 200rpm, 230rpm, 250rpm, 270rpm or 300rpm; the time can be 2-10h, specifically 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h or 10h. In the present invention, wet ball milling is conducive to improving the dispersion effect of graphite, and at the same time, it can improve the mixed dispersion effect of FeS and other raw materials through mechanical alloying, so as to ensure that the sliding bearing copper-based alloy material with excellent comprehensive performance is finally prepared.

[0040] As an embodiment of the present invention, the drying is specifically vacuum drying; the present invention has no special limitation on the conditions of the vacuum drying, as long as sufficient drying is achieved.

[0041] After obtaining the ball-milled material, the present invention presses the ball-milled material to obtain a green body. As an embodiment of the present invention, the pressing pressure may be 300-500 MPa, specifically 300 MPa, 350 MPa, 400 MPa, 450 MPa or 500 MPa. In the embodiment of the present invention, the ball-milled material is placed in a mold for pressing to obtain the green body; the present invention does not specifically limit the material of the mold, and a mold of a material familiar to those skilled in the art may be used.

[0042] After obtaining the green body, the present invention sintered the green body in a protective atmosphere to obtain the sliding bearing copper-based alloy material. As an embodiment of the present invention, the protective atmosphere can be argon and hydrogen, and the volume ratio of argon and hydrogen can be 1:1-3, specifically 1:1, 1:2 or 1:3. As an embodiment of the present invention, the sintering can include sequentially performing the first sintering and the second sintering. As an embodiment of the present invention, the temperature of the first sintering can be 800-850°C, specifically 800°C, 810°C, 820°C, 830°C, 840°C or 850°C; the holding time can be 30-60min, specifically 30min, 40min, 50min or 60min; the heating rate from room temperature to the temperature of the first sintering can be 7-10°C / min, specifically 7°C / min, 8°C / min, 9°C / min or 10°C / min. As an embodiment of the present invention, the temperature of the second sintering can be 900-1000°C, specifically 910°C, 920°C, 930°C, 940°C, 950°C, 960°C, 970°C, 980°C, 990°C or 1000°C, and the holding time can be 30-60min, specifically 30min, 40min, 50min or 60min; the heating rate from the temperature of the first sintering to the temperature of the second sintering can be 3-5°C / min, specifically 3°C / min, 4°C / min or 5°C / min. In the embodiment of the present invention, the sintering is followed by furnace cooling to room temperature. In the embodiment of the present invention, the above two-stage sintering process is used in the above protective atmosphere, which is conducive to ensuring that the sliding bearing copper-based alloy material with excellent comprehensive performance is finally prepared.

[0043] The technical solutions in the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] The particle size of graphite used in the following examples and comparative examples is 5-10 μm; the particle size of FeS is 50-80 μm, and the particle size of other raw materials is 30-100 μm.

[0045] Example 1

[0046] In this embodiment, the sliding bearing copper-based alloy material is prepared from the following raw materials by mass: Ni6%, Sn3%, Zn 2.5%, Cr2%, Mg 1.5%, Zr 0.7%, rare earth (the mass ratio of La and Ce is 1:2) 0.2%, graphite 2%, FeS1%, and the balance Cu.

[0047] The method for preparing the sliding bearing copper-based alloy material comprises the following steps:

[0048] The raw materials for preparing the copper-based alloy material for the sliding bearing are mixed and placed in a ball mill, grinding balls and water are added as a dispersant, wet ball milling is performed for 6 hours at a ball-to-material ratio of 7:1 and a rotation speed of 300 rpm, and then the obtained material is vacuum dried to obtain a ball-milled material;

[0049] The ball-milled material is placed in a mold and pressed at 400 MPa to obtain a green body;

[0050] The green body is subjected to a first sintering and a second sintering in a protective atmosphere in sequence, and then cooled in a furnace to obtain the sliding bearing copper-based alloy material; wherein the temperature of the first sintering is 830°C, the holding time is 30 minutes, and the heating rate from room temperature to the temperature of the first sintering is 8°C / min; the temperature of the second sintering is 950°C, the holding time is 1 hour, and the heating rate from the temperature of the first sintering to the temperature of the second sintering is 5°C / min.

[0051] Embodiments 2 to 6

[0052] The method of Example 1 is used for operation, except that the copper-based alloy material of the sliding bearing in each example is prepared from the formula raw materials shown in Table 1. Other matters not specially explained are carried out according to Example 1.

[0053] Table 1 Raw material formula for preparing copper-based alloy materials for sliding bearings in Examples 2 to 6 (mass percentage, %)

[0054] Raw material types Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Ni 6 6 6 6 6 8 Sn 3 3 3 3 3 2 Zn 2.5 2.5 2.5 2.5 2.5 1.5 Cr 2 2 2 2 2 2.5 Mg 1.5 1.5 1.5 1.5 1.5 1.5 Zr 0.7 0.7 0.7 0.7 0.7 0.7 Rare Earth 0.2 0.2 0.2 0.2 0.2 0.2 graphite 2 1 1.5 2 1 2 FeS 1 2 1.5 2 1 1 Cu margin margin margin margin margin margin

[0055] Comparative Examples 1 to 7

[0056] The method of Example 1 was used for operation, except that the copper-based alloy material of the sliding bearing in each comparative example was prepared from the raw materials with the formula shown in Table 2. Other matters not specially explained were carried out according to Example 1.

[0057] Table 2 Raw material formula for preparing copper-based alloy materials for sliding bearings in Comparative Examples 1 to 7 (mass percentage, %)

[0058]

[0059]

[0060] Test Example 1

[0061] The performance of the copper-based alloy materials for sliding bearings in the embodiments and comparative examples was tested as follows:

[0062] Hardness: Brinell hardness;

[0063] Tensile strength: tested according to GB-T 228.1-2010;

[0064] Radial crushing strength: tested according to GB-T 6804-2008;

[0065] Tribological properties: HT-1000 high temperature friction and wear testing machine was used for evaluation. The dual ball was 316 stainless steel, the load was 5N, the sliding speed was 0.20m / s, the friction radius was 5mm, the sliding distance was 360m, the running time was 30min, and the test temperature was 400℃.

[0066] The test results of the properties of the copper-based alloy materials for sliding bearings in various embodiments and comparative examples are shown in Table 3. The results show that the copper-based alloy materials for sliding bearings of the present invention have excellent anti-friction and anti-wear properties and mechanical properties.

[0067] Table 3 Performance test results of copper-based alloy materials for sliding bearings in various embodiments and comparative examples

[0068]

[0069] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A copper-based alloy material for a sliding bearing, prepared from the following raw materials by mass content: Ni 5~8%; Sn 2.5~3.5%; Zn 2~3%; Cr 1.5~2.5%; Mg 1.2~1.8%; Zr 0.6~0.9%; rare earth 0.1~0.4%; graphite 1~2%; FeS1~2%; and the balance Cu.

2. The sliding bearing copper-based alloy material according to claim 1, characterized in that: Prepared from the following raw materials: Ni 6~7%; Sn 2.8~3.2%; Zn 2.3~2.7%; Cr 1.8~2.2%; Mg 1.4~1.6%; Zr0.7~0.8%; rare earth 0.2~0.3%; graphite 1.3~1.7%; FeS1.3~1.7%; and the balance Cu.

3. The sliding bearing copper-based alloy material according to claim 1 or 2, characterized in that: The rare earth includes La and / or Ce.

4. The sliding bearing copper-based alloy material according to claim 3, characterized in that: The rare earths are La and Ce, and the mass ratio of La to Ce is 1:0.5-2.

5. The method for preparing the copper-based alloy material for sliding bearings according to any one of claims 1 to 4, comprising the following steps: Mixing various raw materials for preparing the copper-based alloy material for sliding bearings, performing wet ball milling, and then drying to obtain ball milled material; Pressing the ball-milled material to obtain a green body; The green compact is sintered in a protective atmosphere to obtain the sliding bearing copper-based alloy material.

6. The preparation method according to claim 5, characterized in that: The ball-to-material ratio of the wet ball milling is 5 to 10:1, the rotation speed is 200 to 300 rpm, and the time is 2 to 10 hours.

7. The preparation method according to claim 6, characterized in that: The dispersant used in the wet ball milling includes one or more of water, ethanol and acetone.

8. The preparation method according to any one of claims 5 to 7, characterized in that: The pressing pressure is 300-500 MPa.

9. The preparation method according to claim 8, characterized in that: The sintering includes a first sintering and a second sintering in sequence; the temperature of the first sintering is 800-850°C, and the insulation time is 30-60 minutes; the temperature of the second sintering is 900-1000°C, and the insulation time is 30-60 minutes.

10. The preparation method according to claim 8, characterized in that: The heating rate from room temperature to the first sintering temperature is 7-10° C. / min, and the heating rate from the first sintering temperature to the second sintering temperature is 3-5° C. / min.

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