1.       The chemical elements

      （1）201 stainless steel sheets elements is 1Cr17Mn6Ni5.

     (2)  201 stainless steel sheet has Mn. For colour, 201 stainless steel sheet colour is dark because of Mn. But it can’t be distinguished with our eyes.

     (3) Because 201 stainless steel sheet has high carbon, 201 stainless steel sheet is hard. When we use knife to scrach the 201 stainless steel surface, 201 will have obvious nick.

    (4) Beause 201 stainless steel sheet has Mn, it will be rusty in the damp air with high salt for a long time.

2.       Using spectrometer

     If we want to distinguish 201 stainless steel sheet, using spectrometer is easy

way. Put it on the stainless steel sheet surface, it will have chemical elements. According with 201 stainless steel sheet chemical elements, we can contrast. But spectrometer price is hundreds of thousands, so few people will buy it.But it can be rent.

3.       Using potion

     We all know the stainless steel test potion, we can distinguish the material of stainless steel sheets when we drop a few drops of potion.This test potion is good. Potion detection is very convenient, accurate and feasible. At present, this kind of identification syrup can be bought online, but it is difficult to buy on the market.