The role of trace metal elements in steel:

16, rare earth (Re): is a good deoxidation, desulfurization agent. Can eliminate or reduce the impact of many harmful elements in steel, improve the quality of steel. The addition of Re in stainless heat-resistant steels can improve the hot-workability of steels. The addition of Re to structural steels can increase their ductility and toughness.

17. Boron (B): "Vitamins" in steel. Can double quenching; increase the hardness and tensile strength of steel; improve the welding performance of steel. Adding 0.1 to 4.5% of B to mild steel has the function of absorbing neutrons.

18, calcium (Ca): can improve the strength of steel and cutting performance. Purification agent in the smelting process. (In addition to oxygen, sulfur, phosphorus, etc.).