Research on high temperature mechanical properties of nitrogen-microalloying steel HRB500E continuous casting billet
To optimize the CC water-cooling technology of nitrogen-microalloying steel HRB500E continuous casting billet and guarantee the quality of the billet,the high temperature mechanical properties of the billet were measured by Gleeble-1500D thermal simulator,the microstructure and morphology of specimen fracture were observed and analyzed,and the fracture mechanism of the billet in different temperature range was also discussed.The results showed that when the strain rate was 1.4 × 10-3/s,the third brittle temperature range of HRB500E billet was 675-750 ℃.The main cause of the brittle fracture was due to precipitation of ferrite at austenite grain boundary,MnS segregation and precipitation of large amount of V(C,N) at grain boundary.The second brittle temperature range did not appear in the billet,and the fracture mode was transgranular fracture at about 1 000 ℃.The first brittle temperature range was above 1 300 ℃.The fracture mode was intergranular fracture,and the main cause was enrichment of O,S,P at the grain boundary,which led to form liquid film.
nitrogen-microalloyingHRB500E steelcontinuous casting billethigh temperature mechanical propertybrittle temperaturefracture
NETL
NSTL
万方数据
维普
