Cause Analysis of Delamination in Tensile Fracture of Low Alloy High Strength Steel
Aiming at the lamination phenomenon of transverse tensile fracture of grade 420MPa low alloys steel plate at room temperature,the macroscopic morphology and microstructure were analyzed by the observation of fracture morphology,non-metallic inclusions and metallographic structure,scanning electron microscope and energy spectrum test,and the causes and influencing factors of the lamination were discussed.The results show that the existence of core segregation and MnS inclusions in the specimen is the main reason for the delamination of tensile fracture.By improving the purity of molten steel,the contents of sulfur,phosphorus and other harmful elements in molten steel are strictly controlled.In combination with the low superheat casting process of continuous casting,reasonable control of casting speed and optimization of controlled rolling and cooling process can effectively reduce the probability of such defects.
low alloy high strength steeltensile fracturelayeringsegregationsuperheat
万方数据
维普
