1. Differences between stainless steel 201 and 202
Differences between 202 stainless steel and 201: 201 and 202 stainless steel are the same 200 series stainless steel, but they are often compared, but they are not very different from 304 and 316 applications.
Related reading: 304 vs 316 Stainless Steel
1. Grade difference.
202 grade is 1Cr18Mn8Ni5N and 201 grade is 1Cr17Mn6Ni5N.
2. Comparison of composition between 201 and 202 stainless steels:
Composition comparison table of 202 and 201 stainless steels
If it really reaches the national standard, the nickel content of 202 is higher than 201 stainless steel, and the price is more expensive than 201 stainless steel.
There will be sellers in the market who say our 202 is cheaper than the 201, so their 202 should be fake.
202 and 201 stainless steels are widely used in construction, decoration and other industries.
2. History of 201 and 202 stainless steel
200 series stainless steel was first developed in the United States as a substitute for 300 series stainless steel during World War II.
At that time, due to the war, nickel as a strategic material was strictly controlled by various countries, and the supply of nickel in the United States was seriously insufficient.
In order to solve the problem of stainless steel production and supply in the case of serious shortage of nickel supply, the United States developed this new austenitic stainless steel series with manganese instead of nickel.
After the end of World War II, the supply of nickel in the United States gradually improved.
Therefore, the production of 300 series stainless steel is no longer restricted by the shortage of raw materials, so the 200 series has not been greatly developed.
After several Indians who participated in the development of 200 series stainless steel returned to India, they brought back the 200 series stainless steel varieties developed in the United States to India based on the fact that India is relatively rich in manganese resources and short of nickel resources.
The successful application of 200 series stainless steel in India is due to the possibility of replacing 304 stainless steel in some specific applications.
3. Advantages and disadvantages of 201 and 202 stainless steel
Difference between 202 stainless steel and 201: In terms of price, 201 is a little cheaper than 202 stainless steel, but both are much cheaper than 304 stainless steel.
Therefore, 201 and 202 stainless steels have obvious price advantages in use scenarios with low requirements for corrosion resistance and impact toughness.
Most of the 200 series stainless steels sold in the Chinese market rarely strictly control the sulfur and carbon content according to the national standard.
Most of them replace part or all of the nickel with manganese (or nitrogen) to produce austenitic stainless steels with lower nickel content.
Disadvantages of 200 series stainless steel (including 201 and 202 stainless steel):
1. The chromium content below 18% cannot reach the balance with the low nickel content, thus forming ferrite.
Therefore, the chromium content in 200 series stainless steel decreases to 13.5%~15%, and in some cases to 13%~14%. Its corrosion resistance cannot be compared with 304 or similar steel.
2. In addition, manganese and, in some cases, copper reduce the role of re-passivation under the common acidic conditions in the corrosion areas of the deposition areas and crevices.
The destruction rate of 200 series steel under these conditions is about 10-100 times that of 304 stainless steel
3. In production, it is often impossible to control the residual sulfur and carbon content in these steels, and the materials cannot be traced to the tide source, even the recycling of 200 series stainless steel materials.
Note: If Cr Mn steels are not described, they will become a dangerous scrap mixed raw material, resulting in unexpected high manganese content in castings.