40Cr－5CrMnMo钢超塑性压接的组织与性能

Structure and Properties of Superplastic Pressure Welding Between 40Cr and 5CrMnMo Steel

采用预先处理及表面处理，４０Ｃｒ－５ＣｒＭｎＭｏ钢在空气炉中可实现超塑性固相压接．压接工艺条件为：温度７１０～７３０℃，应变速率２～３×１０－４ｓ－１、压力５０～８０ＭＰａ．时间３～５ｍｉｎ．压接强度达到基材４０Ｃｒ钢强度。通过接头显微组织分析，提出了钢超塑性固相压接机制为超塑变形的晶粒滑动和原子扩散造成的原始界面消失。

Superplastic pressure welding of steel 40Cr-5CrMnMo, with prior surface after pretreatment,was performed in electro-furnace under the conditions of 710￣730℃、2￣3×10-4s-1, 50￣80MPa,3￣5min.The joints were examined to have similar strength to the steel 40Cr, The microstructure of bonding zone was analyzed by SEM. The micromechanism for superplastic bonding of steels was suggested as the disappearance of original bond interfaces caused by atomic diffusion and grain sliding superplastic deformation.