Study on the geometrical dimensions and mechanical properties of Ti-6Al-4V alloy blade by laser metal deposition

The most advanced metal 3D printing promises to revolutionize the manufacturing industry and has already played their strengths in the field of part repair and surface coating, but they have not yet reached the best operability in the overall manufacturing. The challenge is how to design the process route. Therefore, the entire process of blade design-manufacture-testing was carried out in this paper. The fifth-degree polynomial is used to construct the blade, and on this basis, a CAD model of a thin-walled blade with torsion was established. After the blade was manufactured by LMD, the geometric dimensions and mechanical properties were tested. The test results show that the standard deviation of the blade body part is less than 0.3 mm, which basically meets the design requirements. The Vickers hardness of LDM blades changes continuously along the deposition direction, mainly due to the changes in the structure caused by different cooling rates. The tensile strength of the blade is basically the same in the 0 degrees, 45 degrees, and 90 degrees directions, which is greater than 770 MPa. The elongation in different directions differs more than 5% and has obvious anisotropy, which is mainly caused by the organization structure and the way of unit cell stacking.