Interfacial microstructure and mechanical properties of forging and SLM hybrid manufacturing Ti-6Al-4V parts

Ti-6Al-4V alloy composite samples and tensile parts were formed by SLM with forged Ti-6Al-4V alloy rolled plate as the base material. The microstructure analysis, tensile property test, microhardness test and fracture morphology observation were carried out on the bonding surface. The results show that the forging region and forming region of SLM form a close metallurgical bond, no cracks appear. The vertical and horizontal mixed tensile samples were prepared. The fracture position of vertically mixed tensile samples occurs at the side of the matrix, indicating that the bonding surface strength is higher than that of the matrix. The tensile strength of the horizontal mixed tensile sample reaches 1144.1 +/- 0.5 MPa. The tensile strength of the vertical mixed tensile sample reaches 856.6 +/- 0.4 MPa. The microhardness in SLM zone is the highest at room temperature, between 340 +/- 5HV0.5 and 360 +/- 5HV0.5, that in forging zone is between 300 +/- 5HV0.5 and 350 +/- 5HV0.5. The hardness of heat-affected zone is 330 +/- 5HV 0.5.