#Galvanized pipe # performance requirements
(1) High strength: generally, its yield strength is more than 300mpa.
(2) High toughness: the required elongation is 15% ~ 20%, and the impact toughness at room temperature is greater than 600kj / M ~ 800kj / m. High fracture toughness is also required for large welded components.
(3) Good welding performance and cold forming performance.
(4) Low cold brittle transition temperature.
(5) Good corrosion resistance.
3. Composition characteristics of galvanized pipe
(1) Low carbon: due to the high requirements for toughness, weldability and cold forming performance, its carbon content shall not exceed 0.20%.
(2) Add alloy elements dominated by manganese.
(3) Adding auxiliary elements such as niobium, titanium or vanadium: a small amount of niobium, titanium or vanadium forms fine carbides or carbonitrides in the steel, which is conducive to obtaining fine ferrite grains and improving the strength and toughness of the steel. In addition, adding a small amount of copper (≤ 0.4%) and phosphorus (about 0.1%) can improve the corrosion resistance. Adding a small amount of rare earth elements can desulfurization and degassing, purify steel and improve toughness and process performance.
