阅读说明：本技术 一种提高汽车精锻件耐磨性的方法 (Method for improving wear resistance of automobile precision forging ) 是由 周中亮 徐明传 汪长开 詹光 于 2019-11-03 设计创作，主要内容包括：本发明公开了一种提高汽车精锻件耐磨性的方法,该方法包括如下步骤：a、放置精锻件；b、加温；c、准备涂料；d、喷涂；e、冷却；f、二次加温；g、二次喷涂；h、淬火；i、回火；j、二次冷却,本发明通过a、b、c、d、e、f、g、h、i和j十个步骤对精锻件逐级进行表面处理,改变精锻件的力学性能,提升精锻件的耐磨性。(The invention discloses a method for improving the wear resistance of an automobile precision forging, which comprises the following steps: a. placing the precision forging piece; b. heating; c. preparing a coating; d. spraying; e. cooling; f. heating for the second time; g. secondary spraying; h. quenching; i. tempering; j. and (3) secondary cooling, namely performing surface treatment on the precision forging piece step by step through ten steps of a, b, c, d, e, f, g, h, i and j, so that the mechanical property of the precision forging piece is changed, and the wear resistance of the precision forging piece is improved.)

1. The method for improving the wear resistance of the automobile precision forging is characterized by comprising the following steps:

a. placing a precision forging piece: the precision forging piece is stably fixed on a horizontally placed working table top and is fixed by a fixing piece, so that the precision forging piece is prevented from moving;

b. heating: starting the flame gun, enabling a nozzle of the flame gun to face the outer surface of the precision forging piece, and heating the precision forging piece; heating the outer surface of the precision forging and maintaining the temperature at 300-350 ℃;

c. preparing a coating: melting tungsten carbide powder by adopting a high-temperature heat source to form liquid tungsten carbide, and filling the liquid tungsten carbide into a spraying gun;

d. spraying: uniformly spraying tungsten carbide on the outer surface of the fine forging piece by using a supersonic spraying method, so that the outer surface of the fine forging piece is covered with a tungsten carbide coating;

e. and (3) cooling: placing the precision forging piece in a low-temperature environment of minus 30 ℃ for 3 hours;

f. secondary heating: placing the cooled precision forging on a working table, starting a flame gun to enable a nozzle of the flame gun to face the outer surface of the precision forging, heating the precision forging, and enabling the outer surface of the precision forging to be heated and maintained at 600-650 ℃;

g. secondary spraying: uniformly spraying tungsten carbide on the outer surface of the fine forging piece by using a supersonic spraying method again, so that the outer surface of the fine forging piece is covered with a tungsten carbide coating again;

h. quenching: putting the precision forging subjected to the secondary carburization treatment into quenching equipment for quenching treatment, wherein the quenching temperature is 800-840 ℃;

i. tempering: and (3) putting the quenched and quenched precision forging into tempering equipment for tempering, wherein the tempering temperature is 400-440 ℃.

j. Secondary cooling, namely putting the tempered product into the mixed solution for cooling; and finishing the treatment of improving the wear resistance of the forged piece after cooling treatment.

2. The method for improving the wear resistance of the automobile precision forging according to claim 1, wherein the heating and the secondary heating are carried out in a closed oxygen-isolating manner, and the closed heating is carried out in an inert gas environment.

3. The method of claim 2, wherein the inert gas is one of helium, argon and xenon.

4. The method for improving the wear resistance of the automobile precision forging according to claim 1, wherein the finish forging is required to be evenly coated with butter and stored after the tempering in the step i.

5. The method for improving the wear resistance of the automobile precision forging according to claim 1, wherein the low-temperature environment used for cooling in the step e is sodium chloride solution.

6. The method for improving the wear resistance of automobile precision forgings according to claim 5, wherein the concentration of the sodium chloride solution is 5 to 10 percent.

Technical Field

The invention relates to the technical field of automobiles, in particular to a method for improving the wear resistance of an automobile finish forging.

Background

The precision forging piece is a mechanical element which is provided with teeth on a wheel rim and can be continuously engaged to transmit motion and power, and the precision forging piece is an important part of an automobile. The service life of the automobile precision forging piece is mainly examined by two major indexes, namely the contact fatigue strength of the automobile precision forging piece and the bending fatigue strength of the automobile precision forging piece, wherein the contact fatigue strength and the bending fatigue strength are mainly determined by the properties of the automobile precision forging piece material. The steel grade for the precision forging of the medium and heavy truck in China is more. The existing automobile precision forging piece is serious in abrasion, slow in transmission reaction and high in noise of the precision forging piece during transmission, the service life of the precision forging piece is shortened, the working reliability of the precision forging piece is greatly reduced, meanwhile, the production cost is high, the weight of the precision forging piece is heavy, and the transportation is inconvenient. Therefore, the vibration reduction and the light weight are two important properties of the precision forging piece, the vibration reduction can relieve the precision forging piece abrasion and noise aggravated by vibration of the precision forging piece, the service life of the automobile precision forging piece is prolonged, the light weight not only lightens the total weight of a transmission precision forging piece box, but also is beneficial to reducing the impact, and the sensitivity of system starting and braking is improved.

Disclosure of Invention

Based on the technical problems in the background art, the invention provides a method for improving the wear resistance of an automobile precision forging, so as to improve the wear resistance of the automobile precision forging, and prolong the service efficiency and the service life of the automobile precision forging.

The technical scheme adopted by the invention is as follows:

a method for improving the wear resistance of an automobile precision forging comprises the following steps:

a. placing a precision forging piece: the precision forging piece is stably fixed on a horizontally placed working table top and is fixed by a fixing piece, so that the precision forging piece is prevented from moving;

b. heating: starting the flame gun, enabling a nozzle of the flame gun to face the outer surface of the precision forging piece, and heating the precision forging piece; heating the outer surface of the precision forging and maintaining the temperature at 300-350 ℃;

c. preparing a coating: melting tungsten carbide powder by adopting a high-temperature heat source to form liquid tungsten carbide, and filling the liquid tungsten carbide into a spraying gun;

d. spraying: uniformly spraying tungsten carbide on the outer surface of the fine forging piece by using a supersonic spraying method, so that the outer surface of the fine forging piece is covered with a tungsten carbide coating;

e. and (3) cooling: placing the precision forging piece in a low-temperature environment of minus 30 ℃ for 3 hours;

f. secondary heating: placing the cooled precision forging on a working table, starting a flame gun to enable a nozzle of the flame gun to face the outer surface of the precision forging, heating the precision forging, and enabling the outer surface of the precision forging to be heated and maintained at 600-650 ℃;

g. secondary spraying: uniformly spraying tungsten carbide on the outer surface of the fine forging piece by using a supersonic spraying method again, so that the outer surface of the fine forging piece is covered with a tungsten carbide coating again;

h. quenching: putting the precision forging subjected to the secondary carburization treatment into quenching equipment for quenching treatment, wherein the quenching temperature is 800-840 ℃;

i. tempering: and (3) putting the quenched and quenched precision forging into tempering equipment for tempering, wherein the tempering temperature is 400-440 ℃.

j. Secondary cooling, namely putting the tempered product into the mixed solution for cooling; and finishing the treatment of improving the wear resistance of the forged piece after cooling treatment.

The heating and the secondary heating are carried out in a closed oxygen-isolating mode, and the closed heating is carried out in an inert gas environment.

The inert gas is one of helium, argon and xenon.

And (e) after the tempering in the step i is finished, uniformly coating the precision forging by using butter and storing.

The low temperature environment used for cooling in step e is sodium chloride solution.

The concentration of the sodium chloride solution is 5% to 10%.

The invention has the beneficial effects that:

1. the method for improving the wear resistance of the automobile precision forging piece comprises the steps of placing the precision forging piece; b. heating; c. preparing a coating; d. spraying; e. cooling; f. heating for the second time; g. secondary spraying; h. quenching; i. tempering; j. and the ten steps of secondary cooling are used for carrying out surface treatment on the precision forging piece step by step, so that the mechanical property of the precision forging piece is changed, and the wear resistance of the precision forging piece is improved.

2. According to the method for improving the wear resistance of the automobile precision forging, the precision forging is fixed on the working table top through the fixing piece, so that the precision forging is prevented from moving, spraying work is facilitated, the precision forging is in full contact with the coating, the protection effect of the coating on the precision forging is enhanced, and the wear resistance of the precision forging is improved.

3. According to the method for improving the wear resistance of the automobile precision forging, the heating and the secondary heating are carried out in a closed oxygen isolation mode, the closed heating is carried out in an inert gas environment, impurities and other gases in the air are effectively prevented from being mixed into the coating, the performance of the coating is changed, and the wear resistance effect of the precision forging is influenced.

Drawings

FIG. 1 is a flowchart of a method according to a first embodiment of the present invention;

FIG. 2 is a flowchart of a method according to a second embodiment of the present invention;

FIG. 3 is a flowchart of a method according to a third embodiment of the present invention;

FIG. 4 is a graph comparing the mass wear rates of examples one, two, three and comparative examples.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the examples given herein without any inventive step, are within the scope of the present invention.