A method for surface treatment of metal components

Abstract

The invention discloses a surface treatment method for a metal component. The method comprises the following steps that firstly, the metal component is pretreated; secondly, an alloy permeating agent is prepared; thirdly, alloy permeating is conducted; fourthly, cooling and separation are conducted; and fifthly, alkaline electropolishing is conducted. Compared with the prior art, the surface treatment method for the metal component has the following advantages that the abrasion resistance and impact resistance of the metal component are greatly improved, so that the service life of the metal component is effectively prolonged; in addition, in the treatment process of the metal component, the environment preservation performance is good, and no pollution to the environment is caused.

Description

technical field [0001] The invention relates to a method for surface treatment of metal components. Background technique [0002] Treating the surface of metal components is an effective method to improve the mechanical properties of metal components. At present, there are mainly the following methods for surface treatment of metal components: [0003] 1. Zinc sherardizing process: Put the infiltrating agent and metal components in a zinc sherardizing furnace, heat to about 400 degrees, and zinc atoms penetrate into the metal components. The advantage of the sherardizing process is that the sherardizing layer is relatively thick and its combination with zinc is thermal diffusion, so it is very firm. The disadvantage is that the surface after treatment is gray-black, the appearance is very poor, the surface is very rough and difficult to further process, and its corrosion resistance The performance is also relatively low, and the neutral salt spray test can only be maintaine...

AI Technical Summary

Problems solved by technology

The advantage of the sherardizing process is that the sherardizing layer is relatively thick and its combination with zinc is thermal diffusion, so it is very firm. The disadvantage is that the surface after treatment is gray-black, the appearance is very poor, the surface is very rough and difficult to further process, and its corrosion resistance The performance is also relatively low, and the neutral salt spray test can only be maintained within 300 hours. If you want to improve the salt spray performance, you must increase the thickness of the seepage layer. For many products that require precision matching, such as threaded products, the product will be damaged after increasing the thickness of the seepage layer. The size needs to be increased, and the thread fit clearance needs to be further adjusted, which greatly reduces the reliability of the product during use.

[0004] Second, the electro-galvanizing process: it is to use electrolysis to form a uniform, dense, and well-bonded zinc deposit on the surface of the metal component. Although the electro-galvanized coating is bright, its corrosion resistance is relatively poor, and the thickness is only 5-10um. It is difficult to pass the 120-hour salt spray test

At the same time, the surface hardness of the electro-galvanized layer is only 80HV, and the bonding force and wear resistance are relatively poor. The traditional electro-galvanized process requires pickling, passivation, etc., which will cause serious pollution to water resources.

[0005] Third, hot-dip galvanizing process: immersing metal components in molten zinc solution to attach a zinc layer to the surface to achieve the purpose of anti-corrosion. The advantages of hot-dip galvanizing are high output and higher corrosion resistance than electro-galvanizing. However, the zinc layer on the surface of hot-dip galvanized parts is relatively loose, which will form zinc dross and zinc nodules on the surface of the product, making it difficult to control the dimensional accuracy of the product surface, especially for products that require precise matching of the two component sizes. Zinc dross and zinc nodules will cause product dimensions Difficult to cooperate

It is difficult to pass the neutral salt spray test for 240 hours. The surface hardness of hot-dip galvanizing is only 80HV, and the wear resistance is poor. At the same time, the pre-treatment process of hot-dip galvanizing requires pickling, which will cause serious pollution to the water source. The formula structure will also produce a large amount of three waste pollutants such as sulfur dioxide, nitrogen oxides, monoxide, and soot in the air.