TiAl/40Cr感应钎焊接头界面结构及力学性能分析

以Ag-Cu-Ti为钎料对TiAl与40Cr进行了感应钎焊试验。采用扫描电镜、电子探针和X射线能谱分析仪等分析测试手段对界面组织及生成相进行了分析；测试了接头的抗拉强度及界面生成相的显微硬度。结果表明，钎缝处出现了Ti Al3、Ags,s]、Ti(Cu,Al)2三种反应相，当钎焊温度为1 143~1 183 K时， 接头的界面结构为TiAl/ TiAl3 /TiAl3 + Ags,s]/ Ti(Cu,Al)2 + Ags,s] / Ags,s] + Ag-Cu共晶相/ 40Cr；当钎焊温度为1 223 K时，接头的界面结构为TiAl / Ti(Cu,Al)2+少量Ags,s]/ Ags,s] + Ag-Cu共晶相/ 40Cr。在试验所选的工艺参数范围内，最佳规范为连接温度为1 143 K，保温时间为5 min，此时接头的抗拉强度达到267 Mpa。

RESEARCH ON MECHANICAL PROPERTIES AND MICROSTRUCTURES OF TiAl/40Cr JOINT OBTAINED BY INDUCTION BRAZING METHOD

TiAl and 40Cr is induction brazed with Ag-Cu-Ti filler metal in a vacuum furnace. The microstructure and mech- anical properties of the joints is studied. The kinds of formation phases and the interface structures of the joints are investigated by scanning electron microscopy (SEM), electron probe microanalysis (EPMA) and X-ray diffraction (XRD), the joint strength is determined by tensile testing method and the microhardness of the formation phases is tested. Results show that three formation phases, TiAl3, Ags,s], Ti(Cu,Al)2, have occurred in the brazing seam. The interface structure of the joints brazed at 1 143-1 183 K can be described as TiAl / TiAl3/ TiAl3+Ags,s]/Ti(Cu,Al)2 + Ags,s] / Ags,s] + Ag-Cu eutectic phase / 40Cr and the interface structure of the joints brazed at 1 223 K can be described as TiAl / Ti(Cu,Al)2+ some Ags,s] / Ags,s]+ Ag-Cu eutectic phase / 40Cr. An excellent joint tensile strength as high as 267 MPa is obtained when induction brazed all 143 K for 5 min.