同义词
1)Endothermic gas,叹热型气体(热处理保护气)2)N_2 atmosphere,氮气保护热处理3)Protective atmosphere heat treatment,保护气氛热处理4)atmosphere protection heat treatment,气氛保护热处理5)heat treatment in nitrogen based atmosphere,氮基气氛保护热处理6)pre-treatment in argon atmosphere,氩气保护预热处理
