The main elements of stainless steel are iron, chromium, and nickel. We usually divide stainless steel into nickel-chromium stainless steel and chromium stainless steel. The so-called “stainless iron” actually does not exist. “Stainless iron” is just an irregular name in stainless steel, which is a very unscientific verbal name.
All alloy products of iron elements are called “steel”, such as stainless steel angle steel, which is also called stainless steel angle iron.
There is indeed a difference in composition between stainless steel and “stainless iron”. What we call “stainless iron” does not contain nickel, it is chromium stainless steel. For example, martensitic stainless steel is replaced by iron in the nickel-containing part of the original stainless steel. This type of stainless steel can be attracted by magnets.
However, nickel-chromium stainless steel containing nickel cannot be attracted by magnets.
To give an example in daily life, the cooking utensils used at home are mostly resistant to nickel-free, so-called “stainless iron”. Because the price of nickel is very high, the cost of using nickel-added stainless steel will go up a lot.
The first consideration for high-end cookware is quality.
Nickel-added stainless steel is corrosion-resistant, does not rust, has a compact structure, high finish, and softer colors. Credit Encyclopedia also gives you an idea to not take a magnet with you when buying cooking utensils, try it if necessary, so as not to be fooled.
It is not completely reliable to distinguish between the two based on magnetic permeability alone. Experienced people can also distinguish one from the other from the appearance of the two. The so-called stainless iron is just treatment on the surface of the iron, it is not really stainless.
From the appearance, stainless steel is whitish and shiny (referring to nickel stainless steel, another type of stainless steel is called chromium stainless steel, which has a little tungsten on the surface). The so-called stainless steel surface is only shiny. For those businessmen who have high requirements for materials in industrial use, we still recommend doing a salt spray test on the product or use a spectrum analyzer to avoid disputes.