Why are 410 and 420 called stainless steel?

410 and 420 stainless steel are stainless steel grades produced in accordance with American ASTM standards. 410 is equivalent to my country's 1Cr13 stainless steel, and 420 is equivalent to my country's 2Cr13 stainless steel. Both contain no nickel, hence the name stainless iron.

Stainless iron contains chromium but does not contain nickel. It is also called Cr stainless steel and has certain anti-corrosion capabilities. Stainless iron is not a colloquial term. Generally speaking, stainless steel with ferromagnetic properties mainly refers to the 1Cr17 (ferrite) series and 1Cr13 (martensite) series.

Stainless steel identification method:

1. Steel with a chromium content of more than 12.5% and high resistance to corrosion by external media (acid, alkali and salt) is called stainless steel. According to the structural conditions in the steel, stainless steel can be divided into martensite type, ferrite type, austenitic type, ferrite-austenitic type, and precipitation hardening stainless steel. According to the national standard GB3280-92, there are 55 regulations in total. .

2. In our daily life, we come into contact with two major categories: austenitic stainless steel (some people call it nickel stainless steel) and martensitic stainless steel (some people call it stainless iron). Typical grades of austenitic stainless steel are 0Cr18Ni9, namely "304" and 1Cr18Ni9Ti. Martensitic stainless steel is the stainless steel we use to make knives and scissors. The main grades include 2Cr13, 3Cr13, 6Cr13, 7Cr17, etc.

3. Due to the addition of higher chromium and nickel to the steel (containing chromium of about 18% and Ni of more than 4%), austenitic stainless steel has a structural state called austenite in its internal structure. Tissue is not magnetic and cannot be attracted by magnets. It is often used as decorative materials, such as turbine blades, cutting tools, nozzles, valve seats, valves, measuring tools, bearings, etc.