| 摘要 |
The present invention relates to a method for manufacturing a high manganese hot-dip galvanized steel sheet with excellent coatability and ultra-high strength and to a hot-dip galvanized steel sheet manufactured by said method. One embodiment of the present invention provides a high manganese hot-dip galvanized steel sheet and a method for manufacturing the high manganese hot-dip galvanized steel sheet, the method comprising the steps of: obtaining a cold-rolled steel sheet by cold-rolling a hot-rolled steel sheet by the reduction ratio of 30 to 60%, wherein the hot-rolled steel sheet comprises, by weight%, 0.3 to 1% of C, 8 to 25% of Mn, 0.1 to 3% of Si, 0.01 to 8% of Al, 0.1 to 2% of Cr, 0.01 to 0.2% of Ti, 0.0005 to 0.01% of B, 0.01 to 2% of Ni, 0.06 to 0.2% of Sn, and the remainder being Fe and other inevitable impurities; heating the cold-rolled steel sheet in the condition of a dew point temperature of -30 to -80̊C and a temperature of 450 to 650 ̊C; cooling the heated steel sheet to the temperature of 450 to 500̊C or maintaining the heated steel sheet at the temperature of 450 to 500 ̊C; and performing a hot-dip galvanizing process by dipping the cooled or maintained steel sheet into the hot-dip galvanizing bath which comprises 0.13 to 0.25 weight% of Al and has a temperature of 450 to 500̊C. |
