阅读说明：本技术 一种粉末冶金自润滑含油轴承及其制备方法 (Powder metallurgy self-lubricating oil-retaining bearing and preparation method thereof ) 是由 杨诗钰 兰江 黄钊炫 邱天旭 申小平 于 2020-05-26 设计创作，主要内容包括：本发明属于粉末冶金领域,具体涉及一种粉末冶金自润滑含油轴承及其制备方法。轴承包括环状轴体,在环状轴体的实体内部具有分布不均匀的18.0％～20.0％的可浸油孔隙。制备方法包括将Cu-Sn粉、Ni粉和MoS<Sub>2</Sub>粉均匀混合,外加0.6％硬脂酸锌粉,进行压制成形,其中各组分的重量份数为：Cu 80.1～87.3,Sn 8.9～9.7,Ni 6.0～9.0,MoS<Sub>2</Sub> 1.0～2.0；然后控温800～820℃,在N<Sub>2</Sub>:H<Sub>2</Sub>＝5：1气氛下烧结；进行真空浸油1天；最后进行精整处理。本申请粉末冶金自润滑含油轴承,硬度HV80以上,径向压溃强度170MPa以上,Ni和MoS<Sub>2</Sub>的加入分别提高了青铜基自润滑轴承的力学性能和摩擦学性能,因而提高了青铜基自润滑轴承的使用寿命,拓宽了青铜基自润滑轴承的应用领域。(The invention belongs to the field of powder metallurgy, and particularly relates to a powder metallurgy self-lubricating oil-retaining bearing and a preparation method thereof. The bearing comprises an annular shaft body, and 18.0% -20.0% of oil-submersible pores are distributed unevenly inside the solid body of the annular shaft body. System for makingThe preparation method comprises mixing Cu-Sn powder, Ni powder and MoS 2 The powder is uniformly mixed, 0.6 percent of zinc stearate powder is added, and the mixture is pressed and formed, wherein the weight parts of the components are as follows: 80.1 to 87.3 Cu, 8.9 to 9.7 Sn, 6.0 to 9.0Ni, MoS 2 1.0 to 2.0; then controlling the temperature to be 800-820 ℃ at N 2 :H 2 5: 1, sintering in atmosphere; vacuum oil immersion is carried out for 1 day; and finally, finishing treatment is carried out. The powder metallurgy self-lubricating oil-retaining bearing has the hardness of HV80 or more, the radial crushing strength of 170MPa or more, Ni and MoS 2 The addition of the copper alloy improves the mechanical property and the tribological property of the bronze-based self-lubricating bearing respectively, thereby prolonging the service life of the bronze-based self-lubricating bearing and widening the application field of the bronze-based self-lubricating bearing.)

1. the powder metallurgy self-lubricating oil-retaining bearing is characterized by comprising an annular bearing main body, wherein the bearing main body is provided with 18% -20% of oil-submersible pores which are distributed unevenly.

2. The bearing of claim 1, wherein the bearing body is made of a material having a weight percentage ofCu80.1～87.3％，Sn 8.9～9.7％，Ni 6.0～9.0％，MoS₂1.0～2.0％。

3. A method of manufacturing the powder metallurgy self-lubricating oil-impregnated bearing according to any one of claims 1 to 2, comprising the steps of:

step (1): uniformly mixing Cu powder, Sn powder, Ni powder and MoS₂Calculating the theoretical density of the bearing main body according to the porosity of 25 percent by using the powder and 0.6 percent of zinc stearate powder added, putting the bearing main body into a hydraulic forming machine for press forming, and changing the volume of a finished product by adjusting the height of the bearing main body to reach the theoretical density;

step (2): sintering the product obtained in the step (1) in a copper sintering furnace, controlling sintering conditions to enable powder to be metallurgically connected and to shrink, wherein the overall shrinkage rate is 1.5-2.0%, and the porosity is reduced by 2.5-5.5%;

and (3): and (3) carrying out an oil immersion process on the product obtained in the step (2) under a vacuum condition, so that the oil content of the final bearing main body is 18.0-20.0%.

And (4): and (4) carrying out a finishing procedure on the product obtained in the step (3) to prepare the powder metallurgy self-lubricating oil-retaining bearing.

4. The method according to claim 3, wherein the sintering conditions in step (2) are as follows: sintering atmosphere of N₂:H₂5: 1 atmosphere, the sintering temperature is 800-820 ℃, and the sintering time is 50-60 minutes.

5. The method according to claim 4, wherein the oil immersion time of the oil immersion process is more than 24 hours.

6. The method according to claim 5, wherein the oil immersion process is vacuum oil immersion, and the oil used in the vacuum oil immersion is antiwear hydraulic oil.

7. The method of claim 6, wherein the step (4) of preparing the bearing is performed byThe density is 6.7 to 6.9g/cm³The hardness is more than 80HV, the radial crushing strength is more than 170MPa, and the friction coefficient of the bearing under the oil-containing self-lubricating condition is 0.053-0.078.

Technical Field

The invention belongs to the field of powder metallurgy, and particularly relates to a powder metallurgy self-lubricating oil-retaining bearing and a preparation method thereof.

Background

At present, the improvement of the mechanical property and the tribological property of the oil-retaining bearing is one of the important concerns in the industry, and is used in the high-strength and high-speed working environment. The porosity is difficult to control by the common machining and manufacturing method, and the friction coefficient and the abrasion loss are not beneficial to being effectively reduced.

In addition, the bronze-based oil-retaining bearing has good thermal conductivity, seizure resistance, corrosion resistance and lower friction factor, and can be used in a high-rotation-speed working environment, but compared with the iron-based oil-retaining bearing, the bronze-based oil-retaining bearing has lower strength and load resistance, and cannot be used in a high-strength working environment.

In addition, at present, friction performance of oil-containing bearings is rarely studied, but the application fields of oil-containing bearings are continuously expanded, and the requirements on working environments are continuously strict, so that the oil-containing bearings must have the performances of high strength, low friction coefficient, wear resistance and corrosion resistance.

Disclosure of Invention

The invention aims to provide a powder metallurgy self-lubricating oil-retaining bearing and a preparation method thereof.

The technical solution for realizing the purpose of the invention is as follows: a powder metallurgy self-lubricating oil-retaining bearing comprises an annular bearing body, wherein the bearing body is provided with 18% -20% of oil-submersible pores which are distributed unevenly.

Furthermore, the bearing main body is made of 80.1-87.3 wt% of Cu，Sn8.9～9.7％，Ni 6.0～9.0％，MoS₂1.0～2.0％。

A method for preparing the powder metallurgy self-lubricating oil-retaining bearing comprises the following steps:

step (1): uniformly mixing Cu powder, Sn powder, Ni powder and MoS₂Calculating the theoretical density of the bearing main body according to the porosity of 25 percent by using the powder and 0.6 percent of zinc stearate powder added, putting the bearing main body into a hydraulic forming machine for press forming, and changing the volume of a finished product by adjusting the height of the bearing main body to reach the theoretical density;

step (2): sintering the product obtained in the step (1) in a copper sintering furnace, controlling sintering conditions to enable powder to be metallurgically connected and to shrink, wherein the overall shrinkage rate is 1.5-2.0%, and the porosity is reduced by 2.5-5.5%;

and (3): and (3) carrying out an oil immersion process on the product obtained in the step (2) under a vacuum condition, so that the oil content of the final bearing main body is 18.0-20.0%.

And (4): and (4) carrying out a finishing procedure on the product obtained in the step (3) to prepare the powder metallurgy self-lubricating oil-retaining bearing.

Further, the sintering conditions in the step (2) are as follows: sintering atmosphere of N₂:H₂5: 1 atmosphere, the sintering temperature is 800-820 ℃, and the sintering time is 50-60 minutes.

Further, the oil immersion time of the oil immersion process is more than 24 hours.

Further, the oil immersion process is vacuum oil immersion, and oil used in the vacuum oil immersion is antiwear hydraulic oil.

Further, the density of the bearing prepared in the step (4) is 6.7-6.9 g/cm³The hardness is more than 80HV, the radial crushing strength is more than 170MPa, and the friction coefficient of the bearing under the oil-containing self-lubricating condition is 0.053-0.078.

Compared with the prior art, the invention has the remarkable advantages that:

(1) the oil immersion porosity of the powder metallurgy self-lubricating oil-retaining bearing product is controlled to be 18-20%, the good mechanical property can be ensured, and the sufficient oil content can be ensured to maintain the good tribological property;

(2) the powder metallurgy self-lubricating oil-retaining bearing product uses Cu-10Sn powder as a substrate and Ni as a matrix additive phase, and under the sintering temperature of 800-820 ℃, when the weight of a Ni component reaches 6.0, the hardness can be improved by 65HV, the crushing strength can be improved by 79MPa, the friction coefficient is not changed greatly, but when the weight of the component exceeds 9.0, the improvement amplitude of the hardness and the crushing strength is greatly reduced;

(3) the powder metallurgy self-lubricating oil-retaining bearing product uses Cu-10Sn powder as a substrate and MoS₂As solid lubricant, MoS at a sintering temperature of 820 DEG C₂When the weight of the components reaches 1.0, the friction coefficient is reduced by at least 0.006, the limit PV value is improved by at least 0.61, MoS₂The larger the weight of the component, the better the friction performance, when MoS₂When the weight of the component exceeds 2.0, the mechanical properties begin to decrease sharply. 6.0-9.0 Ni and 1.0-2.0 MoS₂The method effectively solves the problem of insufficient load resistance of the bronze-based self-lubricating oil-containing bearing, improves the tribological performance, prolongs the service life of the oil-containing bearing, and widens the application field of the bronze-based self-lubricating oil-containing bearing.

Drawings

Fig. 1 is a top view of a self-lubricating oil-impregnated bearing of the present invention.

Fig. 2 is a cross-sectional view of a self-lubricating oil-impregnated bearing of the present invention.

Description of reference numerals:

1-chamfer I, 2-bearing body, 3-chamfer II.

Detailed Description

The present invention is described in further detail below with reference to the attached drawing figures.

As shown in fig. 1 and 2, the invention relates to a powder metallurgy self-lubricating oil-retaining bearing. The inner ring and the outer ring of the bearing main body 2 are provided with 45- degree chamfers 1 and 3 with direct edges of 0.5mm, the bearing main body 2 contains pores, and lubricating oil can be released and recovered in the friction process after oil immersion, so that self-lubrication is realized.

The powder metallurgy self-lubricating oil-retaining bearing is prepared from the following components in parts by weight: 80.1 to 87.3 Cu, 8.9 to 9.7 Sn, 6.0 to 9.0Ni, and MoS₂1.0 to 2.0. AThe method for preparing the powder metallurgy self-lubricating oil-retaining bearing comprises the following steps:

(1) uniformly mixing Cu powder, Sn powder, Ni powder and MoS₂Calculating the theoretical density of the bearing main body according to the porosity of 25 percent by using the powder and 0.6 percent of zinc stearate powder added, putting the bearing main body into a hydraulic forming machine for press forming, and changing the volume of a finished product by adjusting the height of the bearing main body to reach the theoretical density;

(2) sintering the product obtained in the step (1) in a copper sintering furnace, controlling sintering conditions to enable powder to be metallurgically connected and to shrink, wherein the overall shrinkage rate is 1.5-2.0%, and the porosity is reduced by 2.5-5.5%;

(3) and (3) carrying out an oil immersion process on the product obtained in the step (2) under a vacuum condition, so that the oil content of the final bearing main body is 18.0-20.0%.

(4) And (4) carrying out a finishing procedure on the product obtained in the step (3) to prepare the powder metallurgy self-lubricating oil-retaining bearing.

Further, the sintering conditions in the step (2) are as follows: sintering atmosphere of N₂:H₂5: 1 atmosphere, the sintering temperature is 800-820 ℃, and the sintering time is 50-60 minutes.

Further, the oil immersion time of the oil immersion process is more than 24 hours.

Further, the oil immersion process is vacuum oil immersion, and oil used in the vacuum oil immersion is antiwear hydraulic oil.

Further, the density of the bearing prepared in the step (4) is 6.7-6.9 g/cm³The hardness is more than 80HV, the radial crushing strength is more than 170MPa, and the friction coefficient of the bearing under the oil-containing self-lubricating condition is 0.053-0.078.