How to distinguish stainless steel

1 Use stainless steel identification reagents to identify

Stainless steel identification reagents can quickly detect 200 series, 300 series, and 400 series stainless steels. Stainless steel needs to be wiped clean (the stainless steel surface must not be damaged).

(1) 201 stainless steel, the droplet turns brown in 1 second;

(2) 202 stainless steel, the droplet turns brownish red in about 15 seconds;

(3) 301 stainless steel, the droplet turns light red after 30 seconds;

(4) 304 stainless steel, the droplet slowly turns light gray in more than 50 seconds.

Generally, stainless steel identification agents are equipped with contrast color swatches, which can identify stainless steel models.

2. Magnetic identification of stainless steel

Austenitic stainless steel is non-magnetic or weakly magnetic, but the chemical composition fluctuates or the processing state is different during the smelting process, and magnetism may appear. After the stainless steel is cold-worked, the structure will also transform to Martensite. The greater the degree of cold-working deformation, the martensite The more the transformation, the greater the magnetic properties of the steel. Stainless steel cannot be judged by magnetism.

3. Identify with copper sulfate

After the surface of the stainless steel is wiped clean, put a drop of water on it, add copper sulfate to rub it, it will not change color, it is stainless steel. If it turns purple, the non-magnetic material is high manganese steel, and the magnetic material is generally carbon steel or low alloy steel.