Stainless steel has many excellent properties such as electrical conductivity, thermal conductivity, strength, toughness, plasticity, wear resistance, castability, and the like. Stainless steel materials are still the most important structural materials, and they are widely used in all aspects of production, life and technology. Stainless steel products are subject to various damages during production and use, such as mechanical wear, biological damage, etching, and the like.
1, the definition of stainless steel etching
The stainless steel etching machine is the damage or deterioration caused by stainless steel under the action of the environment. There are other expressions for the etching of stainless steel. The so-called environment refers to substances that come into contact with stainless steel. For example, naturally occurring atmosphere, sea water, fresh water, soil, etc., as well as raw materials and products for production and daily use. The chemical or electrochemical action of thousands of these substances and stainless steel causes the etching of stainless steel, and in many functional situations, mechanical force, radiation, current, biology, etc. are simultaneously present. The portion of the stainless steel that is etched changes from a simple substance to a compound, causing rust, cracking, perforation, brittleness, and the like. Therefore, in the vast majority of cases, the process of stainless steel etching is a reverse process of metallurgy.
2, stainless steel etching classification
There are many ways to classify.
(1) According to the etching process, there are mainly chemical etching and electrochemical etching. Chemical etching is the damage caused by the direct chemical action of stainless steel and environmental media, and no current is generated during the etching process. For example, stainless steel is etched in high temperature air or chlorine gas, non-electrolyte is used in stainless steel etching machines, and the like. The material from the stainless steel chemical etching is not conductive. Electrochemical etching is damage caused by the electrochemical action of stainless steel in an electrolyte solution, and current is generated during the etching process. The medium that causes the electrochemical etching can conduct electricity. For example, stainless steel is etched in a medium such as an acid, a base, a salt, a soil, or a seawater. The main difference between electrochemical etching and chemical etching is that it can be decomposed into two separate and simultaneous cathode and anode processes, and chemical etching does not. Electrochemical etching is more common and common than chemical etching.
[2] According to the shape of the stainless steel etching machine and the distribution of the etching zone, it is divided into full etching and partial etching. Full etching means etching the surface of a thousand stainless steel. The etch is uniformly etched at the same level throughout the etch, and there are also non-uniform etches with different etched etches in different etch regions. The etching that occurs when cleaning steel and aluminum equipment with pickling is generally a thousand uniform etching. While etching is concentrated primarily on certain areas of the stainless steel surface, it is referred to as local etching. Although the etching amount of such etching is not large, the local etching speed is large, which may cause serious damage to the device or even explosion, and therefore, the damage is greater. Stainless steel can undergo different local etches under different environmental conditions. For example, pitting, slit etching, stress etching, intergranular etching, wear etching, and the like. The etching is further divided into high temperature etching and normal temperature etching according to etching environmental conditions: dry etching and wet etching.
