中國有色金屬學報(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 13 Special 1 May 2003 |
（State Key Laboratory of Advanced Welding Production Technology,
Harbin Institute of Technology, Harbin 150001, China）
Abstract:Vacuum brazing of a TiAl-based alloy to a middle-carbon steel was carried out at 1173K for 0.5-40min with a Ag-Cu filler metal. The formation phases and interface structure of the joints were investigated by SEM, EPMA and XRD, and the joint strength was determined by the shear test method. Three formation phases, Ti(Cu, Al)2, Ag(s.s.) (Ag-based solid solution) and TiC, occurred in the brazing seam, and the interface structure of the joints can be expressed as TiAl/Ti(Cu, Al)2+Ag(s.s.)/Ag(s.s.)/TiC/steel, but TiC does not occur and a small amount of Ag-Cu eutectic exists in the joints brazed for a shorter time. The shear tests show that the room-temperature strength and fracture location of the brazed TiAl/steel joints change with brazing time. When the joint was brazed at 1173K for less than 2min, the shear strength was up to 150MPa and the fracture occurred within the Ti(Cu, Al)2+Ag(s.s.) zone.
Key words: interface structure; shear strength; brazing; TiAl-based alloy; carbon steel
