Microstructure and Strength of TiC Cermet/Cast Iron Brazed with Ag-Cu-Zn Filler Metal
The brazing of TiC cermet to cast iron was carried out at 1223K for 5-30min using Ag-Cu-Zn filler metal. Formation phase, interface structure and shear strength of the joint were investigated. The results show: There occur three formation phases: Cu-base solid solution, FeNi and Ag-base solid solution in TiC cermet/cast iron joint. The amounts of Cu-base solid solution and FeNi increase and the amount of Ag-base solid solution decreases as brazing time increasing. When brazing time is 20min, the highest shear strength of the joint is up to 292.0MPa and the interface structure of the joint can be expressed as TiC cermet/Cu-base solid solution + FeNi/Ag-base solid solution + a little Cu-base solid solution + a little FeNi/Cu-base solid solution + FeNi/cast iron.