Different compositions of TC4/TC11 functional gradient materials interface by wire arc additive manufacturing

Titanium alloy is widely utilized in diverse industries due to its exceptional specific strength, making it a material with significant potential for advancement. Nevertheless, homogeneous materials are inadequate to meet the demands of various applications. Functional gradient materials (FGMs) have garnered increasing interest for their ability to tailor materials and structures. The continuous transition in FGMs often offers a more uniform and well-connected interface. However, there remains a lack of comprehensive research on the transition interface. In this study, TC4/TC11 double-alloy materials were produced using double-wire additive manufacturing. The wire feeding rates were adjusted to create materials with varying compositions. The grain morphologies, microstructures, and mechanical properties were examined. It was observed that as the TC11 content increased, the grain size decreased, the β content rose, the ultimate tensile strength improved, and the elongation decreased. Additionally, analysis of the fracture morphologies revealed that the dimples became smaller, indicating characteristics of ductile fracture. Following the solid solution aging heat treatment, it is observed that the α phase increases in size, and the mechanical properties are enhanced. These observations indicate that double-wire additive manufacturing can produce diverse interfaces. Furthermore, the heat treatment process has been shown to enhance the material properties, thus establishing an experimental foundation for FGMs.