Effect of Healing on Mechanical Properties by the Combined Treatment of Pulse Current and Laser Applied to Deep Crack in Titanium Alloy

The effect of healing on mechanical properties is investigated by the combined treatment of pulse current and laser applied to deep crack in titanium alloy, as they have different advantages in crack healing. The micro-hardness test results show that after electropulsing treatment the hardness between substrate and healing areas is significantly different, and the higher hardness is observed in healing areas. After laser remelting treatment, the hardness of healing areas generated in electropulsing treatment process is reduced and the hardness among remelting zone-heat affected zone-substrate shows a gradual decreasing trend. The mechanical test results show that, for electropulsing treatment specimen, the tensile property decreases and the fatigue property increases, both the mechanical performance curves show the secondary fracture properties. While for the specimen experienced the combined treatment of pulse current and laser, both the tensile and fatigue properties are improved obviously. The detour and joule heating effect of pulse current and the remelting effect of laser are the main reasons to realize crack healing.