CN103537668A - Powder metallurgy bearing material and preparation method thereof - Google Patents

Abstract

The invention discloses a powder metallurgy bearing material. The powder metallurgy bearing material is characterized by being composed of, by weight, 5.2-5.5 parts of tungsten, 2.1-2.3 parts of cobalt, 5.7-5.9 parts of nickel, 1.2-1.5 parts of titanium, 0.2-0.5 part of boron, 72-75 parts of ferrum, 3.2-3.5 parts of silicon, 1.2-1.4 parts of graphite, 1.7-1.9 parts of manganese, 5.2-5.6 parts of chromium, 2.3-2.5 parts of zinc stearate, 1.2-1.4 parts of microcrystalline wax, 0.4-0.5 part of tungsten carbide, 0.2-0.4 part of titanium carbide and 1-2 parts of auxiliary agents. The graphite is added to raw materials of the powder metallurgy bearing material, so that abrasion resistance and lubricity of a bearing are enhanced, and the bearing made of the powder metallurgy bearing material is compact in structure and good in microstructure, has very few holes, and has excellent structural rigidity, hardness, fatigue resistance and tensile strength; addition of the nickel enhances toughness and the elasticity modulus of alloy, thereby playing a prominent role in guaranteeing geometric stability of the bearing.

Description

A kind of P/m Bearing Materials and preparation method thereof

Technical field

The present invention relates to field of powder metallurgy, particularly a kind of P/m Bearing Materials and preparation method thereof.

Background technology

Powder metallurgy be produce metal dust or with metal dust (or mixture of metal dust and non-metal powder) as raw material, through being shaped and sintering, produce the industrial technology of metal material, composite and all kinds goods.At present, PM technique has been widely used in the fields such as traffic, machinery, electronics, Aero-Space, weapons, biology, new forms of energy, information and nuclear industry, becomes one of branch of tool development vitality in new material science.That PM technique possesses is significantly energy-conservation, economize material, excellent performance, Product Precision is high and the series of advantages such as good stability, is very suitable for producing in enormous quantities.In addition, part material and the also available PM technique manufacture of complex parts that with conventional cast method and machining process, cannot prepare, thereby enjoy the attention of industrial quarters.Powder metallurgy structural part product material composition is not limited by melting, both can add alloying component, can add other structural constituent yet, and adjusts as requested in sizable scope, and then can reach the effect of mating with steel part in mechanical property.

Bearing steel is for manufacturing the steel of ball, roller and bearing ring.Bearing is bearing pressure and frictional force greatly when work, uniform hardness and wearability so require bearing steel to have height, and high elastic limit.The distribution of the content of the uniformity of the chemical composition of bearing steel, non-metallic inclusion and distribution, carbide etc. being required all very strict, is to require one of the strictest steel grade during all iron and steel are produced.Within 1976, the ISO of International Standards Organization includes some general bearing grades of steel in international standard, and bearing steel is divided into: four classes such as full through hardening type bearing steel, surperficial constrictive type bearing steel, stainless bearing steel, high-temperature bearing steel are totally 17 grades of steel.General bearing steel is mainly high-carbon-chromium bearing steel, and phosphorus content 1% left and right, adds the chromium of 1.5% left and right, and contains a small amount of manganese, the hypereutectoid steel of element silicon.Chromium can improve heat treatment performance, improve quenching degree, structural homogenity, temper resistance, can improve again rustless property and the grinding performance of steel.But when chromium content surpasses 1.65%, after quenching, can increase retained austenite in steel, reduce hardness and dimensional stability, increase the inhomogeneities of carbide, reduce impact flexibility and the fatigue strength of steel.For this reason, the chrome content general control in high-carbon-chromium bearing steel is below 1,65%.Only have the chemical composition in strict control bearing steel, could obtain the microstructure and hardness that meets bearing performance by heat treatment step.

Summary of the invention

The object of this invention is to provide P/m Bearing Materials that a kind of rust-preventing characteristic is good, wearability is high, hardness is large and preparation method thereof.

In order to realize object of the present invention, the present invention passes through following scheme implementation:

, by the raw material of following weight portion, made: W5.2-5.5, Co2.1-2.3, Ni5.7-5.9, Ti1.2-1.5, B0.2-0.5, Fe72-75, silicon 3.2-3.5, graphite 1.2-1.4, manganese 1.7-1.9, chromium 5.2-5.6, zinc stearate 2.3-2.5, microwax 1.2-1.4, tungsten carbide 0.4-0.5, TiC0.2-0.4, auxiliary agent 1-2;

Described auxiliary agent is made by the raw material of following weight portion: iron powder 3-4, zinc oxide 1-2, isopropyl distearyl acyl-oxygen base Aluminate 1-2, kaolin 2-3, polyvinyl alcohol 2-3, carbon fiber 1-2, ferrous sulfate 2-3, sodium phosphate trimer 1-2, mica powder 3-4, crosslinking agent TAIC1-2, zinc stearate 1-2.Preparation method mixes iron powder, zinc oxide, ferrous sulfate, sodium phosphate trimer, mica powder, grind to form 200-300 order powder, then add isopropyl distearyl acyl-oxygen base Aluminate to mix, under 10-15Mpa, be pressed into blank, then, send at 920-950 ℃ and calcine 3-4 hour, cooling after, be ground into 300-400 order powder, mix with other residual components, be heated to 60-70 ℃, under 1200-1500 rev/min, stir 1-2 hour, obtain.

P/m Bearing Materials of the present invention, by following concrete steps, made:

(1) W, Co, Ni, Ti, B, Fe, manganese, chromium are mixed, add in suitable quantity of water, send into ball milling in ball mill, obtain 250-400 order powder, then, spraying is dry, oven dry, under 6-8Mpa pressure, is pressed into bulk, then under nitrogen protection atmosphere 550-650 ℃ carry out sintering 8-10 hour, will be after the crushing material after sintering cross 200-400 mesh sieve;

(2) other residual components is mixed;

(3) at 52-56 ℃, after mixing and stirring 60-90 minute, pack step (1), (2) material into mould, be pressed into base;

(4) pressed compact is placed in sintering furnace, with 6-8 ℃/min of speed, is warming up to sintering 2-3 hour under 800-850 ℃ of condition; Then with 5-7 ℃/min of speed, be warming up to sintering 2-3 hour under 1050-1150 ℃ of condition; Then, then be cooled to 725-750 ℃ with 10-12 ℃/min of speed, be incubated after 1-2 hour, then to be cooled to 320-340 ℃ with 8-10 ℃/min of speed again, be incubated after 2-3 hour, in air, slow cooling is to room temperature.

In raw material of the present invention, increase graphite, increased wearability and the lubricity of bearing, the bearing dense structure of manufacture, microstructure is good, and seldom, the rigidity of structure, hardness, fatigue performance, tensile strength properties are good for hole; Owing to having improved toughness and the elastic modelling quantity of alloy adding of Ni of the present invention, this has outstanding role to ensureing bearing products geometrical stability.

The specific embodiment

Below by instantiation, the present invention is described in detail.

, by the raw material of following weight portion, made: W5.2, Co2.1, Ni5.7, Ti1.2, B0.2, Fe72, silicon 3.2, graphite 1.2, manganese 1.7, chromium 5.2, zinc stearate 2.3, microwax 1.2, tungsten carbide 0.4, TiC0.2, auxiliary agent 1;

Described auxiliary agent by following weight portion (kilogram) raw material make: iron powder 4, zinc oxide 2, isopropyl distearyl acyl-oxygen base Aluminate 1, kaolin 3, polyvinyl alcohol 3, carbon fiber 1, ferrous sulfate 3, sodium phosphate trimer 1, mica powder 3, crosslinking agent TAIC2, zinc stearate 1.Preparation method mixes iron powder, zinc oxide, ferrous sulfate, sodium phosphate trimer, mica powder, grind to form 200-300 order powder, then add isopropyl distearyl acyl-oxygen base Aluminate to mix, under 10-15Mpa, be pressed into blank, then, send at 920-950 ℃ and calcine 3-4 hour, cooling after, be ground into 300-400 order powder, mix with other residual components, be heated to 60-70 ℃, under 1200-1500 rev/min, stir 1-2 hour, obtain.P/m Bearing Materials of the present invention, by following concrete steps, made:

(1) W, Co, Ni, Ti, B, Fe, manganese, chromium are mixed, add in suitable quantity of water, send into ball milling in ball mill, obtain 250-400 order powder, then, spraying is dry, oven dry, under 6-8Mpa pressure, is pressed into bulk, then under nitrogen protection atmosphere 550-650 ℃ carry out sintering 8-10 hour, will be after the crushing material after sintering cross 200-400 mesh sieve;

(2) other residual components is mixed;

(3) at 52-56 ℃, after mixing and stirring 60-90 minute, pack step (1), (2) material into mould, be pressed into base;

(4) pressed compact is placed in sintering furnace, with 6-8 ℃/min of speed, is warming up to sintering 2-3 hour under 800-850 ℃ of condition; Then with 5-7 ℃/min of speed, be warming up to sintering 2-3 hour under 1050-1150 ℃ of condition; Then, then be cooled to 725-750 ℃ with 10-12 ℃/min of speed, be incubated after 1-2 hour, then to be cooled to 320-340 ℃ with 8-10 ℃/min of speed again, be incubated after 2-3 hour, in air, slow cooling is to room temperature.

Through detection, the hardness of bearing of the present invention: HRC66; Tensile strength: 1590MPa.

Claims (2)

1. a P/m Bearing Materials, it is characterized in that, by the raw material of following weight portion, made: W5.2-5.5, Co2.1-2.3, Ni5.7-5.9, Ti1.2-1.5, B0.2-0.5, Fe72-75, silicon 3.2-3.5, graphite 1.2-1.4, manganese 1.7-1.9, chromium 5.2-5.6, zinc stearate 2.3-2.5, microwax 1.2-1.4, tungsten carbide 0.4-0.5, TiC0.2-0.4, auxiliary agent 1-2;

Described auxiliary agent is made by the raw material of following weight portion: iron powder 3-4, zinc oxide 1-2, isopropyl distearyl acyl-oxygen base Aluminate 1-2, kaolin 2-3, polyvinyl alcohol 2-3, carbon fiber 1-2, ferrous sulfate 2-3, sodium phosphate trimer 1-2, mica powder 3-4, crosslinking agent TAIC1-2, zinc stearate 1-2;

Preparation method mixes iron powder, zinc oxide, ferrous sulfate, sodium phosphate trimer, mica powder, grind to form 200-300 order powder, then add isopropyl distearyl acyl-oxygen base Aluminate to mix, under 10-15Mpa, be pressed into blank, then, send at 920-950 ℃ and calcine 3-4 hour, cooling after, be ground into 300-400 order powder, mix with other residual components, be heated to 60-70 ℃, under 1200-1500 rev/min, stir 1-2 hour, obtain.

2. P/m Bearing Materials according to claim 1, is characterized in that, by following concrete steps, is made:

(1) W, Co, Ni, Ti, B, Fe, manganese, chromium are mixed, add in suitable quantity of water, send into ball milling in ball mill, obtain 250-400 order powder, then, spraying is dry, oven dry, under 6-8Mpa pressure, is pressed into bulk, then under nitrogen protection atmosphere 550-650 ℃ carry out sintering 8-10 hour, will be after the crushing material after sintering cross 200-400 mesh sieve;

(2) other residual components is mixed;

(3) at 52-56 ℃, after mixing and stirring 60-90 minute, pack step (1), (2) material into mould, be pressed into base;

(4) pressed compact is placed in sintering furnace, with 6-8 ℃/min of speed, is warming up to sintering 2-3 hour under 800-850 ℃ of condition; Then with 5-7 ℃/min of speed, be warming up to sintering 2-3 hour under 1050-1150 ℃ of condition; Then, then be cooled to 725-750 ℃ with 10-12 ℃/min of speed, be incubated after 1-2 hour, then to be cooled to 320-340 ℃ with 8-10 ℃/min of speed again, be incubated after 2-3 hour, in air, slow cooling is to room temperature.