Laser Treatment of Titanium Alloys

The structural and phase states of surface layers of the titanium VT1-0, VT3-1, VT-6 and VT-8 alloys after laser treatment in various gas environments, VT25-U alloy after twist extrusion and subsequent laser treatment, and VT1-0 alloy after laser alloying with powders of pure elements Fe, Co, Ni are investigated via the x-ray and metallographic analysis methods.As shown, the mentioned types of treatments lead to an increase in the surface-layers' microhardness values.The influence of the surrounding gas atmosphere and the titanium-alloy chemical composition on the structureformation processes during their laser melting and on the microhardness value of the treated layers is analysed.The effect of laser treatment of the surface of sintered single-phase powder titanium VT1-0-type alloys on the porosity level in the melting zone is investigated.As established, the microhardness in the laser-melting zone of the VT25U alloy exceeds the samples' microhardness after heat treatments and twist extrusion.Therefore, the presented laser surface-treatment modes act as an effective method of titanium-alloy surface treatment, since they have a qualitative effect on structure that, in turn, leads to an improvement in the mechanical characteristics of the surface layers.