Effect of electroshocking treatment on microstructure and mechanical properties of near β titanium alloy manufactured by Laser Melting Deposition

Abstract

Thin-wall specimens of near-β titanium alloy Ti-55531 were manufactured by laser melting deposition (LMD), followed by the post-processing using the electroshock treatment (EST). The results show that the microstructure of the as-manufactured alloy is mainly composed of fine columnar grains and equiaxed grains, showing a unique structure of alternating short columnar grains-equiaxed grains-short columnar grains. EST is shown to change the microstructure and grain size of the specimens. Besides phase variation, EST can also reduce the orientation concentration and weaken the texture. Meanwhile, the lattice constant and the microscopic strain were increased after EST. From the tensile test results, the yield strength and tensile strength increased, and the elongation decreased after EST. The results showed that EST is an effective approach for optimizing the microstructure and improving the mechanical properties of LMD near-β titanium alloy.