Structuring of the Ti6Al4V alloy surface by pulsed laser remelting

Abstract

Abstract In this work, we present experimental data on the structure, chemical composition and wear resistance of a titanium alloy Ti6Al4V after pulsed laser treatment. The material was investigated to get a better understanding of the nature of laser melting, ablation of the surface layer by using nanosecond, picosecond, and femtosecond lasers. Melting and subsequent rapid solidification forms a new changed microstructure of the Ti6Al4V surface layer. This rapid solidification of the surface layer affects the new microstructure as well as its surface’s topography (texture). It is shown that using different laser’s pulse parameters the desired surface topography (texture) of the Ti6Al4V can be obtained. The laser treatment with femtosecond and picosecond pulse allows creating periodical micro/nano structures on the surface. These structure are characterized by good wear resistance as compared with the non-texturized surface of Ti6Al4V. In the case of nanosecond laser surface treatment of the Ti6Al4V elements, it is possible to obtain the strongly extended surface of Ti6Al4V elements in the form of metal-oxide foam that is also characterized with good wear resistance. The laser treatment with femtosecond and picosecond pulse allows creating periodical micro/nano structures on the surface. These structure are characterized by good wear resistance. In the case of nanosecond laser surface treatment of the Ti6Al4V elements, it is possible to obtain the strongly extended surface of Ti6Al4V elements in the form of metal-oxide foam. Analysis of the foam microstructure shows that the α-Ti phase was transformed mostly into β-Ti, and is significantly fragmented.