Abstract: The ductility map of 304HC stainIess was determinae by using the Gleeble-1500dy-namic thermal-mechanical simulator.The effect of Cu on the hot ductility of 304HC stainless steel was analyzed and the mathematical model of resistance to deformation was estoblished.The microstructur,inclusion and fracture surface wer studied by using the methad of microstructure analysis,scanning,eneryy spectrum and electron microscope.The results show that Cu has effect on the hot uctility,and the hot ductility of 304HC stainless steel decrease with the increase of content of Cu.The deformation temperature also has much effect on the hot ductility,the suitable defor-mation temperature are 1100-1200℃.The reason of it is that the Cu rich chemical compounds were precipitated from austenite phase during cooling.The Cu rich chem-ical compounds are brittle substance such as Cu2S,Cu2O and ε-Cu etc.

Key words: 304HC stainless steel, hot ductility, brittle compounds,