What is the effect of carbon equivalent on welding?
The greater the carbon equivalent, the greater the tendency to harden the welding material, and the cold crack is likely to occur in the welding area.Carbon equivalent is related to hardening and cold crack tendency due to welding heat:When the carbon equivalent is large, the martensite structure which is easy to harden in the welding heat affected zone is sensitive to crack and hydrogen quenching. Hardening causes more lattice defects. In the condition of stress and thermal imbalance in the weld, the lattice defect is called the crack source, which increases the tendency of cold crack in the weld.
Carbon equivalent is the conversion of various alloying elements in steel to carbon content! Carbon and alloying elements in steel have different effects on weldability of steel. Carbon has the greatest impact, and other alloy elements can be converted into carbon to estimate the weldability of the welded material. The converted sum is called the carbon equivalent! In Li Guang is used in carbon steel Q235, so if you just want to know welding business, ha ha, can put the carbon steel as the approximation of the carbon equivalent, carbon equivalent higher welding performance worse!
The carbon equivalent of less than 0.4%, good weldability; in 0.4~0.6%, poor weldability, welding preheating and other measures to prevent cracks; more than 0.6 words, when welding needs higher temperature and strict technical measures! PS: carbon equivalent =C+Mn/6+ (Ni+Cu) /15+ (Cr+Mo+V) /5, Q235 carbon content in 0.14%~0.22% between, widely used by the company seems to be Q235B, carbon content between 0.12~0.20%
