阅读说明：本技术 一种汽车用粉末冶金不锈钢零件的制备 (Preparation of powder metallurgy stainless steel part for automobile ) 是由 陈风华 于 2018-07-04 设计创作，主要内容包括：为了改善粉末冶金零件的硬度、耐磨性,设计了一种汽车用粉末冶金不锈钢零件。采用316L气雾化不锈钢粉末为原料,经过配料、球磨、干燥、制粒、成形、球磨工艺成功制备了具有优异力学性能的汽车用粉末冶金不锈钢零件。其中,所研制的粉末冶金视镜底座各项性能指标均已达到进口件的相应的要求,可投入批量生产,实现了该零件国产化大批量生产。所研制产品具有一般不锈钢材料的金属颜色,具有表面光泽、致密无毛刺,其粗糙度均匀且美观,表明均已达到进口件的外观质量水平。所制得的汽车用粉末冶金不锈钢零件,其硬度、致密化程度、抗弯强度都得到大幅提升。本发明能够为制备高性能的汽车用粉末冶金不锈钢零件提供一种新的生产工艺。(In order to improve the hardness and the wear resistance of the powder metallurgy part, the powder metallurgy stainless steel part for the automobile is designed. 316L gas atomization stainless steel powder is used as a raw material, and the automobile powder metallurgy stainless steel part with excellent mechanical property is successfully prepared through the processes of material mixing, ball milling, drying, granulating, forming and ball milling. Wherein, various performance indexes of the developed powder metallurgy sight glass base reach the corresponding requirements of an inlet piece, and the developed powder metallurgy sight glass base can be put into mass production, thereby realizing the domestic mass production of the part. The developed product has the metal color of common stainless steel materials, has glossy surface, is compact and burr-free, has uniform roughness and attractive appearance, and shows that the product reaches the appearance quality level of an inlet piece. The hardness, densification degree and bending strength of the prepared powder metallurgy stainless steel part for the automobile are greatly improved. The invention can provide a new production process for preparing high-performance powder metallurgy stainless steel parts for automobiles.)

1. The preparation raw materials of the powder metallurgy stainless steel part for the automobile comprise: 316L of gas atomized stainless steel powder.

2. The powder metallurgy stainless steel part for the automobile according to claim 1, wherein the powder metallurgy stainless steel part for the automobile is prepared by the steps of: weighing and proportioning original powder according to an experimental design scheme, pouring the weighed and proportioned powder into a ball mill for wet grinding, after the ball mill is finished, carrying out vacuum drying on the prepared granules, then adding a forming agent for granulation, adding the prepared powder into a single-column hydraulic machine for press forming, wherein the pressing pressure is 950MPa, then putting the powder into a vacuum sintering furnace for sintering, the sintering temperature is 1350 ℃, and the heat preservation time is 60 min.

3. The powder metallurgy stainless steel part for the automobile according to claim 1, wherein the inspection step of the powder metallurgy stainless steel part for the automobile comprises: the physical-mechanical property, the density and the apparent hardness are detected according to the general standard of powder metallurgy materials, the measurement of the strength, toughness and plasticity of the base of the rearview mirror is used by being fixedly bonded on the windshield through organic binder, the stress is small (only kilogram level), the strength is larger than the consolidation force of the binder, the problem that the part loses efficacy due to insufficient strength does not exist in the practical application, as long as the sintered part reaches the corresponding indexes of hardness, density and appearance of an inlet part, the granularity analysis adopts a MASTER2000 granularity analyzer, the surface roughness is measured by a TAL1000 surface profile instrument, the microstructure is observed by a Leica metallographic microscope, the hardness is measured by a DH100 type micro Vickers hardness tester, the tensile property is measured by a CM510 type universal testing machine, the fracture appearance is observed by a scanning electron microscope, and the phase analysis is analyzed by a D8 type X-ray diffractometer.

4. The powder metallurgy stainless steel part for the automobile according to claim 1, wherein through comprehensive detection, various performance indexes of the developed powder metallurgy sight glass base all reach corresponding requirements of an inlet piece, and the powder metallurgy sight glass base can be put into mass production, the density of the developed base part for the automobile is 7.2 +/-0.1 g/cm3, the hardness is not less than 60HRB, and all reach corresponding indexes of the inlet piece, so that the domestic mass production of the part is realized, and the developed product of the powder metallurgy stainless steel part for the automobile has the metal color of common stainless steel materials, has surface gloss, compactness and no burr, has uniform and attractive roughness, and indicates that all reach the appearance quality level of the inlet piece.

Technical Field

The invention relates to a powder metallurgy material, in particular to a preparation method of a powder metallurgy stainless steel part for an automobile.

Background

Powder metallurgy is a process technique for producing metal powder or metal powder (or a mixture of metal powder and nonmetal powder) as a raw material, and then forming and sintering the raw material to produce metal materials, composite materials and various products. The powder metallurgy method has similar places to the production of ceramics and belongs to the powder sintering technology, so a series of new powder metallurgy technologies can also be used for preparing ceramic materials. Due to the advantages of the powder metallurgy technology, the powder metallurgy technology becomes a key for solving the problem of new materials, and plays a significant role in the development of the new materials.

Stainless steel is short for stainless acid-resistant steel, and steel grade which is resistant to weak corrosive media such as air, steam and water or has stainless property is called stainless steel. Stainless steel is often classified into: martensitic steel, ferritic steel, austenitic-ferritic (duplex) stainless steel, precipitation hardening stainless steel, and the like. In addition, the paint can be divided into the following components: chromium stainless steel, chromium nickel stainless steel, chromium manganese nitrogen stainless steel and the like. The term stainless steel is not intended to refer to just one type of stainless steel, but rather to more than a hundred industrial types of stainless steel, each of which has been developed to have good properties in its particular application. The addition of molybdenum further improves atmospheric corrosion, particularly corrosion resistance to chloride-containing atmospheres. Stainless steel refers to steel which resists corrosion by weak corrosive media such as air, steam, water and the like and chemical corrosive media such as acid, alkali, salt and the like, and is also called as stainless acid-resistant steel.

Disclosure of Invention

The invention aims to improve the hardness and the wear resistance of powder metallurgy parts, and designs a powder metallurgy stainless steel part for an automobile.

The technical scheme adopted by the invention for solving the technical problems is as follows:

the preparation raw materials of the powder metallurgy stainless steel part for the automobile comprise: 316L of gas atomized stainless steel powder.

The preparation steps of the powder metallurgy stainless steel part for the automobile are as follows: weighing and proportioning the original powder according to an experimental design scheme, and pouring the weighed and proportioned powder into a ball mill for wet grinding. After the ball milling is finished, the prepared granules are dried in vacuum, and then a forming agent is added for granulation. And adding the prepared powder into a single-column hydraulic press for pressing and forming, wherein the pressing pressure is 950 MPa. And then placing the mixture into a vacuum sintering furnace for sintering, wherein the sintering temperature is 1350 ℃, and the heat preservation time is 60 min.

The detection steps of the powder metallurgy stainless steel part for the automobile are as follows: the physical-mechanical properties, density and apparent hardness are detected according to the general standard of powder metallurgy materials. The strength, toughness and plasticity of the rearview mirror base are measured, the rearview mirror base is fixedly connected to the windshield through the organic binder, the stress is small, the strength of the rearview mirror base is larger than the fixing force of the binder, and the problem that parts lose efficacy due to insufficient strength does not exist in practical use. As long as the sintered part meets the corresponding criteria of hardness, density and appearance of the inlet piece. The particle size analysis adopts a MASTER2000 particle size analyzer, the surface roughness adopts a TAL1000 surface profile meter to measure, the microscopic structure adopts a Leica metallographic microscope to observe, the hardness adopts a DH100 type micro Vickers hardness tester to measure, the tensile property adopts a CM510 type universal tester to measure, the fracture morphology adopts a scanning electron microscope to observe, and the phase analysis adopts a D8 type X-ray diffractometer to analyze.

According to the powder metallurgy stainless steel part for the automobile, through comprehensive detection, various performance indexes of the developed powder metallurgy sight glass base reach corresponding requirements of an inlet piece, and the powder metallurgy sight glass base can be put into batch production.

The density of the developed base part of the powder metallurgy stainless steel part for the automobile is 7.2 +/-0.1 g/cm3, the hardness is more than or equal to 60HRB, and the density reaches the corresponding index of an inlet piece. Realizes the domestic mass production of the parts.

The product developed by the powder metallurgy stainless steel part for the automobile has the metal color of a common stainless steel material, has surface gloss, is compact and burr-free, has uniform roughness and attractive appearance, and is shown to reach the appearance quality level of an inlet piece.

The invention has the beneficial effects that:

316L gas atomization stainless steel powder is used as a raw material, and the automobile powder metallurgy stainless steel part with excellent mechanical property is successfully prepared through the processes of material mixing, ball milling, drying, granulating, forming and ball milling. Wherein, various performance indexes of the developed powder metallurgy sight glass base reach the corresponding requirements of an inlet piece, and the developed powder metallurgy sight glass base can be put into batch production. The hardness, densification degree and bending strength of the prepared powder metallurgy stainless steel part for the automobile are greatly improved. The invention can provide a new production process for preparing high-performance powder metallurgy stainless steel parts for automobiles.

Detailed Description