When brown rust spots appear on the surface of stainless steel pipes, people are amazed: "Stainless steel does not rust, and rusted is not stainless steel. Is there a problem with the steel?". This is a one-sided misconception about the lack of understanding of stainless steel. Stainless steel can also rust under certain conditions.

Stainless steel pipes have the ability to resist air oxidation - stainless, and also have the ability to resist corrosion in media containing acids, alkalis and salts - that is, corrosion resistance. However, the size of its corrosion resistance varies with the chemical composition of the stainless steel itself, the mutual state, the conditions of use and the type of environmental media. For example, 304 stainless steel pipe has excellent rust resistance in dry and clean air, but if it is moved to the seaside area, it will rust quickly in the sea fog containing a lot of salt. Therefore, in coastal areas near the seaside, stainless steel pipes are rarely used as guardrails, but when used, stainless steel materials that are more corrosion-resistant than 304 stainless steel pipes, such as 430, are used.

Therefore, it is not any kind of stainless steel that can resist corrosion and rust in any environment. Stainless steel of any material may rust. When brown rust spots appear on the surface of stainless steel, people are amazed: "Stainless steel does not rust, and if it rusts, it is not stainless steel. Is there a problem with the steel?". This is a one-sided misconception about the lack of understanding of stainless steel. Stainless steel can also rust under certain conditions.