Why not easy to rust stainless steel?

'Rust' really is corrosion or rust, is due to the steel surface and the oxygen from the atmosphere, water and acid, alkali, salt and other substances caused by chemical or electrochemical the role of color known as rust or corrosion. The material of the surface is 'rust' is iron oxide. 1. Why is not easy to rust, stainless steel and its added 12 within the matrix. More than 5% of chromium. In oxidizing corrupt corrosion medium, chromium can make quickly born a dense layer of steel surface passivation membrane, prevent the metal substrate was damaged. When the content of chromium in 12. More than 5%, forming a dense layer of the stability of the passivation film, rust resistance leap consolidation, greatly enhance the corrosion resistance ability, this is why the chromium content in stainless steel to more than 12%. 2. Chromium stainless steel add in at the same time, to add to put the right amount of alloy elements such as Ni, Mo, V, rust resistance stronger. So on the rust resistance, austenite size stainless steel than martensite stainless steel is strong. Second level is the corrosion resistance of stainless steel with carbon and chromium content, surface treatment status. Stainless steel along with the progress of the carbon content, the antirust performance degradation, 3 cr13 rust resistance is less than 2 cr13. With the progress of content in steel, anti-rust performance. Surface treatment and state influence rust resistance at the same time. Knife cut the surface plating chromium, electrolytic polishing, mirror polishing, manual polishing abrasive belt, rust resistance decreasing. To be rust stainless steel knife cut, mainly is to don't damage the stainless steel knife cut surface passivation membrane. With good as soon as possible after clean. Dry can. Try not to contact with acid, alkali salt. 3. About 13% - 18% chromium content in stainless steel, nickel content is about 8% - 11%, these two kinds of metal elements in corrosion medium with high corrosion resistance, so the oxidizing reaction (stainless steel is generally not Rust) 。 A: now the plight of the stamping parts