Generally use the following methods to distinguish the quality of stainless steel sculpture:
After pickling stainless steel sculpture, the surface is bright and white:
The chrome-nickel stainless steel is silver-white and jade-colored; the chrome-stainless steel is slightly grayish and slightly glossy; the chrome-manganese-nitrogen stainless steel has a slightly lighter color than the chrome-nickel stainless steel.
The surface color of the unwashed stainless steel sculpture: chrome-nickel steel is brownish white; chrome steel is brownish black; chrome-manganese nitrogen is black, (these three colors refer to the heavier oxidized color). Cold-rolled, non-annealed chrome-nickel stainless steel with reflective white surface. Stainless steel is generally pickled except for Yuan Steel.
Identification with copper sulfate:
The method is to remove the oxide layer on the steel, put a drop of water, rub it with copper sulfate, if it does not change color after rubbing, it is generally stainless steel; if it turns purple red: non-magnetic is high manganese steel, magnetic is generally ordinary steel Or low alloy steel.
Identification with magnetite:
Magnets can basically distinguish between two types of stainless steel.
Because chrome stainless steel can be attracted by magnets under any condition; chrome-nickel stainless steel sculptures are generally non-magnetic in the annealed state, and some may be magnetic after cold working.
However, high-manganese steel with higher manganese content is non-magnetic; the magnetic condition of chrome-nickel-nitrogen stainless steel is more complicated: some are non-magnetic, some are magnetic, some are non-magnetic in the longitudinal direction and magnetic in the horizontal surface. Therefore, although the magnet can basically distinguish between chromium stainless steel and chrome-nickel stainless steel, it cannot correctly distinguish some special-purpose steel grades, and it is impossible to distinguish the specific steel grades.
Identification by chemical qualitative method
The chemical qualitative method is an identification method for identifying whether or not nickel is contained in a magnetic stainless steel door material.
The method is to dissolve the small piece of stainless steel in the aqua regia, dilute the acid solution with clean water, add the ammonia water, and then gently inject the nickel reagent. If there is a red velvety material floating on the liquid surface, it means that the stainless steel contains nickel; if there is no red velvet material, it means that there is no nickel in the stainless steel (but because the nickel content in the stainless steel is low, generally only a few percent, nickel The content is not easy to reveal or determine, and it is generally necessary to use the standard sample experiment several times before it can be mastered).