Corrosion and wear of metals are divided into two forms according to the principle of corrosion; one is electrochemical corrosion, which is due to the action of electrolyte, and local current is generated; the other is chemical corrosion, which is due to the action of dry gas or non-conductive liquid medium the result of. The damage rate of metals caused by electrochemical corrosion is faster, and the serious damage caused by corrosion and wear is *ly caused by electrochemical corrosion, while the rate of damage to metals by chemical corrosion is relatively slow.
In order to prevent corrosion and wear, it is better to use anti-corrosion alloys, stainless steel, etc. as materials for manufacturing parts, and use carbon products as corrosion-resistant materials. From an economic and technical point of view, it is often used to add a gold or non-metallic protective layer on the surface of the part, such as zinc, chromium, nickel, tin, copper, aluminum, lead by hot dip, electroplating or metal spraying. Such as metal materials are compounded on the metal surface, or paint (paint, varnish, mineral oil, petroleum jelly, paraffin solution, etc.) is applied on the surface of the parts as an anti-corrosion layer.