CHARACTERIZATION OF SELECTIVE LASER MELTING 3D-PRINTED Ti64 ALLOY

Tóm tắt

Tensile testing Ti64 alloy samples were 3D printed using SLM (Selective Laser Melting) technology. The main printing parameters were as follows: a laser spot diameter of 180 µm, a hatch spacing of 140 µm, a scanning speed of 1600 mm/s, a laser power of 380 W, a layer thickness of 45 µm, and a continuous printing strategy with alternating layer angles of 45°. The microstructure of the printed sample has a significant influence on its properties. Hence, this study aims to investigate the microstructure and properties of 3D-printed Ti64 alloy objects produced using SLM technology. Various analytical techniques and equipment were used to study the surface morphology, fracture surface, microstructure, and hardness of the 3D-printed Ti64 alloy samples, including an optical microscope, digital optical microscope, X-ray diffraction, scanning electron microscope with an EDS probe, and HV hardness tester. The results indicate that the printed sample primarily consists of the α/α' phase, with an average hardness of approximately 343 HV, an elastic modulus of 24.34 GPa, a yield strength of 93.5 MPa, an ultimate tensile strength of 1049.4 MPa, and an elongation of 12.8%. The printed sample’s surface exhibits high roughness and contains numerous porous defects, and mechanical properties that are inferior to those of conventionally manufactured Ti64 alloy.