1. Low -carbon: Due to the high requirements of toughness, welding, and cold shape performance, the carbon content does not exceed 0.20%.
2. Add the alloy element based on manganese.
3. Add supplementary elements such as titanium, titanium: A small amount of titanium, titanium, or tadpoles forms fine carbides or carbon nitride in steel, which is conducive to obtaining small ferrite grains and improving the strength and toughness of steel. In addition, adding a small amount of copper (≤0.4%) and phosphorus (about 0.1%) can improve corrosion resistance. Add a small amount of rare earth elements to desulfurize, remove gas, purify steel, and improve toughness and process performance.
