Interfacial structure and mechanical property of Al₂O₃ and Invar brazed joint

This paper introduces a brazing process between Al₂O₃ ceramic and Invar alloy.Al₂O₃ can be brazed with Invar effectively.The interfacial structure of Al₂O₃/Invar joint can be expressed as:Invar/Ag（s,s）+Cu（s,s）+Fe₂Ti（zone Ⅰ）/Ag（s,s）+Cu（s,s）+Fe₂Ti+NiTi+Cu₃Ti（zone Ⅱ）/Ag（s,s）+Cu（s,s）+Cu₂Ti+Al（s,s）+TiC+TiO（zone Ⅲ）/Al₂O₃.The maximum shear strength of 139 MPa was measured for as-brazed Al₂O₃/Invar joint brazed at 850℃ for 25 min or 900℃ for 15 min.