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We have the following identification methods for heat-resistant steels:

1. To identify the heat-resistant steel imported or ordered by the steel mill, it is generally only necessary to check the marks on the steel or package according to the quality certificate of the imported or steel mill. Generally, the manufacturer of heat-resistant steel will carry out furnace test in the production process, and the content of each element will be added properly.

2. To distinguish chromium stainless steel, chromium nickel stainless steel and chromium manganese nitrogen stainless steel, the identification method is as follows:

Color identification After pickling, the surface color of stainless steel is silvery white and bright: chrome nickel stainless steel is silver white with jade color; chrome stainless steel is slightly gray with weak luster; the color of chromium manganese nitrogen stainless steel is similar to that of chromium nickel stainless steel. The surface color of stainless steel without pickling: chrome nickel steel is brown white, chromium steel is brown black, chromium manganese nitrogen is black (these three colors refer to the color with heavy oxidation). The surface of Cr Ni stainless steel is silvery white and reflective.

The two kinds of stainless steel can be basically distinguished by the use of magnet. Because chromium stainless steel in any state can be attracted by magnets; chromium nickel stainless steel in the annealing state is generally non-magnetic, after cold processing, some will be magnetic. But the high manganese steel with high manganese content is nonmagnetic; the magnetic situation of chromium nickel nitrogen stainless steel is more complex: some are non-magnetic, some are magnetic, some are non-magnetic in longitudinal plane and magnetic in transverse plane. Therefore, although magnetite can basically distinguish chromium stainless steel and chromium nickel stainless steel, it can not correctly distinguish some special steel grades, let alone specific steel grades.

Identification by copper sulfate Remove the oxide layer on the steel, put a drop of water and wipe it with copper sulfate. If it does not change color, it is generally stainless steel; if it turns purple red, the non-magnetic is high manganese steel, and the magnetic one is ordinary steel or low-alloy steel.

For the special properties of steel, we also need to take the following three methods for identification.

Identification of ground flowers Grinding identification is to grind stainless steel on the polishing machine and observe its spark. If the spark is linear and has more dense knots, it is high manganese steel or manganese nitrogen steel with high manganese content; if there is no knot, it is chromium steel or chromium nickel stainless steel.

Chemical qualitative identification of a simpler method is to use stainless steel liquid medicine!