Microstructure and mechanical properties of CP-Ti subjected to UIT

Abstract

The ultrasonic impact treatment (UIT) effect on microstructure and mechanical properties of commercial purity titanium (CP-Ti) was studied. The microstrucrure was investigated by X-ray diffraction analysis and optical profilometer New View 6200. The microhardness of CP-Ti specimens was measured by microhardness tester with the Vickers pyramid. It was found that UIT of CP-Ti specimens led to severe plastic deformation of surface layer with a thickness equals to 120 [mu]m. This was accompanied by an increase in compressive residual stresses, a growth of the microhardness, a crystallographic texture change and a rise of density of deformation twins in surface layers of titanium specimens. It was shown that the deformation twins play a determining role in microstructure and mechanical properties changes of the surface layer of titanium specimens.