·Silicon (Si): In carbon steel, the silicon content is generally less than 0.4%. Silicon can dissolve in ferrite and has a strengthening effect (it can make the steel dense, 

improve strength and hardness). At the same time, it will also reduce the toughness and plasticity of the steel. When the content is small, its effect is not obvious.

·Manganese (Mn): In carbon steel, the manganese content is generally 0.25%~0.8%. Most of manganese dissolves in ferrite to form a substitutional solid solution. 

Therefore, it has a solid solution strengthening effect that helps to generate texture structure, increase firmness, and strength, and wear resistance.

·Carbon (C): It exists in all steels and is the most important hardening element. It helps to increase the strength of steel.

·Titanium (Ti): Titanium can refine grains, make the organization dense, and improve the comprehensive mechanical properties of steel

·Chromium (Cr): Chromium is a commonly used alloying element. Adding chromium to steel with low carbon content can increase the strength and hardness of 

the steel. Increase wear resistance, hardness, and most importantly, corrosion resistance. Stainless steels with more than 12% are considered stainless steels. 

But if not properly maintained, all steel will rust.

·Nickel (Ni): When the nickel content is less than 6%, the steel has high strength and high toughness. When the nickel content is 8% to 11%, it can be combined with 

chromium to form nickel-chromium stainless steel. When the nickel content exceeds 20%, it can become heat-resistant steel.