Titanium alloy components fabrication by laser depositing TA15 powders on TC17 forged plate: Microstructure and mechanical properties

Abstract The manufacturing of titanium alloy components is of great significance for many industrial applications. High-performance titanium alloy parts are generally produced by a serial operation of hot forging process and extensive machining. Recently, additive manufacturing (AM) technologies such as direct laser deposition (DLD) has been developed to produce net-shape components. In this study, the parts were fabricated by depositing TA15 titanium alloy powders via DLD process on forged TC17 titanium alloy plates. Microstructure, microhardness and tensile properties of as-fabricated sample were examined. By using digital image correlation (DIC), the strain fields as well as the global strain behavior of the tensile specimen have been analyzed. The sample consists of three typical zones: the laser deposited zone (LDZ), the forged substrate zone (SZ), and the heat affected zone (HAZ) with good metallurgical bonding. Superfine basketweave microstructure forms within β grains in LDZ and HAZ because of fast cooling rate. The as-fabricated specimens have good tensile properties with an average ultimate tensile strength of 1027 MPa and average elongation of 4.57%. Non-uniform local strain concentration occurs in LDZ, while no strain concentration is found in HAZ and SZ. The remarkable non-uniformity of plastic strain is ascribed to different microstructures.