There are 0Cr 18Ni9 and SUS304 in the market, of which 0Cr 18Ni9 generally represents national standard production, 304 generally represents ASTM standard production, and SUS 304 represents Japanese standard production.
304 is a general-purpose stainless steel, which is widely used to manufacture equipment and parts that require good comprehensive performance (corrosion resistance and formability). In order to maintain the inherent corrosion resistance of stainless steel, steel must contain more than 18% chromium and more than 8% nickel. 304 stainless steel is a stainless steel brand produced according to American ASTM standard.
Extended data:
For 304 stainless steel, Ni element in its composition is very important, which directly determines the corrosion resistance and value of 304 stainless steel.
The most important elements in 304 are Ni and Cr, but they are not limited to these two elements. Specific requirements are stipulated by product standards. It is generally judged in the industry that as long as the Ni content is more than 8% and the Cr content is more than 18%, it can be considered as 304 stainless steel. This is why this kind of stainless steel is called 18/8 stainless steel in the industry.
In fact, the relevant product standards have very clear regulations on 304, and these product standards have some differences for different shapes of stainless steel. The following are some common product standards and tests.
If you want to determine whether a material is 304 stainless steel, you must meet the requirements of every element in the product standard. As long as one does not meet the requirements, it cannot be called 304 stainless steel.
International stainless steel marking method:
The American Iron and Steel Association uses three numbers to represent various standard grades of malleable stainless steel. These include:
① Austenitic stainless steel is marked with serial numbers of 200 and 300. For example, some common austenitic stainless steels are marked with numbers of 20 1, 304, 3 16 and 3 10.
② Ferritic and martensitic stainless steels are represented by 400 series numbers.
③ ferritic stainless steel is marked with 430 and 446, and martensitic stainless steel is marked with 4 10, 420 and 440C.
④ Duplex (austenite-ferrite), stainless steel, precipitation hardening stainless steel and high alloy with iron content less than 50% are usually named by patent names or trademarks.
References:
Baidu Baike -304 Stainless Steel