STUDY ON HIGH TEMPERATURE MECHANICAL PERFORMANCE OF 60Mn STEEL

This paper studies high temperature mechanical performance of 60Mn steel by methods of solidifying on Gleeble-2000 experimental machine. ZDT (zero ductility temperature) and ZST (zero strength temperature) have been determined. Under the strain rate of 4×10-4/s, there exist two low ductility temperature regions for the tested within the temperature range from steel melting points to 750℃, i.e. RegionⅠfrom the melting points to 1 300℃ and Region Ⅲ from 925℃ to 750℃. In Region Ⅲ, the ductility loss is mainly resulted from the precipitations of nitrides of Al, Nb, etc. at the austenite boundaries in single γ phase temperature range and the formation of the film-like proeutectoid ferrites along the γ grain boundaries in γ＋α two-phase temperature range. By taking measures of precisely controlling steel N, Al concentrations and adopting reasonable secondary cooling pattern interior quality of steel will be advanced.