Stainless steel is the abbreviation of stainless acid-resistant steel. Steel that is resistant to weak corrosive media such as air, steam, and water or is stainless is called stainless steel; while steel that is resistant to chemical corrosion media (chemical corrosion such as acid, alkali, salt, etc.) The type of steel is called acid-resistant steel.

Due to the difference in chemical composition between the two, their corrosion resistance is different. Ordinary stainless steel is generally not resistant to corrosion by chemical media, while acid-resistant steel is generally stainless. The word "stainless steel" does not simply refer to one kind of stainless steel, but refers to more than one hundred industrial stainless steels, each of which is developed to have good performance in its specific application field. The key to success is to first understand the application and then determine the correct steel grade. There are usually only six types of steel relevant to building construction applications. They all contain 17 to 22% chromium, and the better steel types also contain nickel. Adding molybdenum can further improve the atmospheric corrosion resistance, especially the corrosion resistance of chloride-containing atmosphere.

Generally speaking, the hardness of stainless steel is higher than that of aluminum alloy, and the cost of stainless steel is higher than that of aluminum alloy.