16Mn-0.5C강의 열간연성 거동 평가

This work assesses the hot ductility behavior of high manganese steel under hot working conditions. Reduction of area (RA) behavior of 16 Mn-0.5 C steel was investigated to consider it for production in a slab and subsequent hot rolling process. All specimens were machined from the as-cast slab. A hot ductility test was accomplished by a cast simulator through a temperature range of 650 ℃-1200 ℃ with 50 ℃ intervals. The obtained RA values ranged between 30% and 60%, with a maximum at 850℃, and this is far from the general RA behavior of low carbon steel. This result could be attributed to the fact that the specimen is fully austenitic through all test temperatures, and that there is no ferrite at the low temperature end and reduced dynamic recrystallization at the high temperature end. Microstructural evaluation of the fractured specimen revealed that the deformation was concentrated at the grain boundary, and there was little matrix deformation. These results suggest that the grain boundary sliding is the basic cause of the fracture and low values of hot ductility in high manganese steel.