Effect of high energy laser processing on defect and structural phase state of titanium products made by additive technologies

Abstract

The microstructure, physical, and mechanical characteristics of 3D-printed metal products can be improved with high-energy heat treatment included in the manufacturing process. In the present study, Ti-6Al-4V titanium alloy products were 3D-printed with electron beam melting of wire of appropriate composition, while surface laser treatment of 3D-printed material was studied to determine the potential of microstructure modification and characteristics improvement. It was found that certain laser processing modes make it possible to eliminate micro defects (pores) in the samples that are harmful to structural materials. The obtained results also open the prospect of creating 3D-printed metal parts with specified profiles of physical and chemical properties, including gradients, as they model the change in material properties depending on the depth of the deposited layer during high-energy processing of each layer during its application. As demonstrated, both the condition of 3D printing as the velocity of deposition and thickness of each layer, the chemical composition and amount of impurities added to the matrix material during deposition, and the high-energy processing (heating or remelting) parameters are important to form the phase composition and mechanical properties of the final products. The high-energy processing also can be used to control the physicochemical properties of the product’s surface.