Abstract:The microstructure and tensile properties of TC17/TC11 dual alloy fabricated with direct laser melting deposition method using two connecting processes (direct connection and gradient connection) were investigated. The results show that, according to composition changes, the TC17/TC11 dual alloy can be divided into three parts: uniform TC17 zone, transition zone and uniform TC11 zone. The as-deposited microstructure of uniform TC17 and TC11 zones shows cyclic layer-like characteristics. For direct connection process, there exists a extremely narrow transition zone between TC17 and TC11 zones. Sharp changes of both chemical composition, microstrucuture and microhardness are found between uniform TC17 and TC11 zones. For gradient connection process, the transition zone encompasses a wider region in which continuous changes of chemical composition and microhardness is found. The intermediate microstructure which is different from TC17 and TC11 emerges in the gradient transition zone. Room temperature tensile tests show that all as-deposited dual alloy samples regardless of connecting process are fractured in the TC11 zone, with approximate tensile strengths and dispersed elongations.