What are the differences between photovoltaic bracket bolts and ordinary iron bolts? The steel and iron refining processes are carried out using redox reactions, but the two are very different in the reaction object. Ironmaking is to reduce iron. In steelmaking, excess carbon and other impurities in pig iron are removed. So iron and steel are distinguished by their carbon content. Iron-carbon alloys with carbon content below 2% are steel, and those with carbon content above 2% are called iron. So from a metallurgical point of view, there is no such thing as stainless iron.
Yangang is widely used because of its toughness, elasticity and rigidity. The most common reason for most consumers to buy is that stainless steel will not rust, and the criterion is whether it will be attracted by magnets.
From our analysis, as far as rust is concerned, rust is not resistant to corrosion. The main element that determines the corrosion resistance of stainless steel is chromium. Steels with a chromium content of 10.5% or more will not rust. At this time, the oxidation of chromium with the corrosive medium will form an oxide film on the surface, which can prevent basic further corrosion.
Isn't stainless steel attracted by magnets? Of course not necessarily, the alloying elements added during smelting are different, and there is a difference between magnets being attracted and not being attracted. There are more than 100 types of stainless steel due to the different alloy content, which can be divided into:
Austenite: If different proportions of chromium and nickel are added to the molten steel, the austenitic steel is stainless steel that cannot be attracted by magnets;
Ferrite: If chromium and a small amount of nickel (or no nickel) are added to the molten steel, the resulting steel is ferritic stainless steel that the magnet can absorb;
Martensite: The main alloying elements are chromium, iron and carbon.
Rhenium is magnetic except for austenitic stainless steel. In other words, in addition to austenitic stainless steel, other types of stainless steel will be attracted by the magnet.
Stainless steel models are divided into:
200 series austenite (chrome-nickel-manganese)
300 series austenite
400 Series Ferrite
500 series heat-resistant chromium alloy
600 series precipitation hardened stainless steel
The more than one hundred kinds of stainless steel have different characteristics. Which equipment is used for which material is manufactured. This is what the material engineer chooses according to the characteristics of the product:
Ferrite: Chromium 12% --- 30% corrosion resistance is better than other stainless steel
Martensite: high strength, poor plasticity and weldability.
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