Niobium is a commonly used microalloying element for hot-rolled ridged steel bars,which has the effect of refining austenite grains and precipitation hardening.Compared with vanadium,niobium has a lower price and a better cost performance.However,due to its element characteristics,it is easy to form penetrating cracks in the cooling process of the billet,and the steel cracking during rolling leads to the piling-up of steel.In this paper,the crack formation mechanism of niobium microalloying casting billet is studied,and the crack problem of casting billet is effectively solved due to the results of optimizing the composition of molten steel,low superheat casting,secondary cooling process optimization,etc.The rate of 10 thousand tons of pile steel caused by the crack of casting billet is reduced from 1.32 to 0.
关键词
铌微合金化/裂纹/机理/堆钢
Key words
minor Nb alloying/crack/mechanism/piling-up of steel
维普
万方数据