1. Carbon (C) .Carbon is the most important chemical element affecting the cold plastic deformation of steel. The higher the carbon content, the higher strength of steel, and the lower of cold plasticity. It has been proved that for every 0.1% increase in carbon content, the yield strength increases about 27.4Mpa; the tensile strength increases about 58.8Mpa; and the elongation decreases about 4.3%. So the carbon content in steel has a great impact on the cold plastic deformation performance of steel.
2. Manganese (Mn). Manganese reacts with iron oxide in steel smelting, mainly for deoxidation of steel. Manganese reacts with iron sulfide in steel, which can reduce the harmful effect of sulfur on steel. The formed manganese sulfide can improve the cutting performance of steel. Manganese can improves the tensile strength and yield strength of steel , reduces the cold plasticity, which is unfavorable to the cold plastic deformation of steel. However, manganese has an adverse effect on the deformation force The effect is only about 1/4 of carbon. Therefore, except for special requirements, the manganese content of carbon steel should not exceed 0.9%.
3. Silicon (Si). Silicon is the residue of deoxidizer during steel smelting. When the silicon content in steel increases 0.1%, the tensile strength increases about 13.7Mpa. When the silicon content exceeds 0.17% and the carbon content is high, it has a great impact on the reduction of cold plasticity of steel. Properly increasing the silicon content in steel is beneficial to the comprehensive mechanical properties of steel, especially the elastic limit, it can also increase the resistance of steel Erosive. However, when the silicon content in steel exceeds 0.15%, non-metallic inclusions are formed rapidly. Even if the high silicon steel is annealed, it will not soften and reduce the cold plastic deformation properties of the steel. Therefore, in addition to the high strength performance requirements of the product, the silicon content should be reduced as much as possible.
4. Sulfur (S). Sulfur is a harmful impurity. The sulfur in steel will separate the crystalline particles of metal from each other and cause cracks. The presence of sulfur also causes hot embrittlement and rust of steel. Therefore, the sulfur content should be less than 0.055%. The high quality steel should be less than 0.04%.
5. Phosphorus (P). Phosphorus has strong work hardening effect and serious segregation in the steel, which increases the cold brittleness of the steel and makes the steel vulnerable to acid erosion. Phosphorus in the steel will also deteriorate the cold plastic deformation ability and cause product cracking during drawing. The phosphorus content in the steel should be controlled below 0.045%.
6. Other alloy elements. Other alloy elements in carbon steel, such as Chromium, Molybdenum and Nickel, exist as impurities, which have far less impact on the steel than carbon, and the content is also extremely small.
Post time: Jul-13-2022