After cleaning and welding, there will be black, yellow and blue scales on the weld bead, which should be cleaned to keep the primary color of stainless steel. Protection is to form a transparent hard film on the surface to isolate the pollution and corrosion of stainless steel by air and water, which can effectively prevent metal from rusting.

Stainless steel is the abbreviation of stainless and acid-resistant steel, and the steel resistant to weak corrosive media such as air, steam and water or stainless steel is called stainless steel; Steel resistant to chemical corrosive media is called acid-resistant steel. The word "stainless steel" refers not only to one kind of stainless steel, but to 100 kinds of industrial stainless steel.

Each stainless steel developed has good performance in its specific application field. The key to success is to find out the purpose first, and then determine the correct steel grade. There are usually only six kinds of steel related to the application field of building construction.