| 摘要 |
A high manganese steel sheet, hot rolled steel sheet, cold rolled steel sheet, galvanized steel sheet and manufacturing methods thereof are provided to produce a steel sheet for vehicle with high tensile strength over 800MPa, elongation ratio over 30%, and excellent deep drawability. A high manganese steel sheet comprises C 0.3~0.9 weight%, Mn 15~30 weight%, Al 0.01~4.0 weight%, Si 0.1~1.0 weight%, P less than 0.05 weight%, S less than 0.01 weight%, and N less than 0.04 weight%. The steel sheet also includes at least one selected from the group consisting of Nb 0.02~0.1 weight%, Ti 0.01~0.1 weight%, and V 0.025~0.5 weight%. The micro-structure of the high manganese steel is austenite single phase structure. A manufacturing method of the high manganese steel sheet comprises hot-rolling at 850~1000°C, winding at 700°C or below, and cold-rolling at the reduction rate of 30~80%. |
