分别借鉴脉冲电流对深层裂纹愈合效果良好及激光对浅层裂纹愈合效果明显的优势，用脉冲电流及激光对钛合金中的深层裂纹进行复合处理。脉冲电流处理过程中，绕流效应使得裂尖处产生了较高的温升并形成了局部压应力。脉冲电流处理结束后，深层裂纹中出现了部分愈合区域，电子探针检测显示愈合区内元素分布均匀，电子背散射衍射检测显示愈合区内主要为细小的针状马氏体。经过脉冲电流与激光复合处理后，钛合金中深层裂纹愈合效果明显。激光重熔使得上部裂纹愈合良好并形成了重熔区-热影响区-基体的结构。在距离重熔区较近位置处，由脉冲电流形成的愈合区呈现出明显的柱状晶结构。
As the pulse current is effective on deep crack healing and laser had more advantage in shallow crack healing, so the combined treatment of pulse current and laser is applied to deep crack in titanium alloy. During the treatment of pulse current, high temperature and local compressive stress are generated on crack tip under the detour effect. Some healing areas appear after pulse current treatment, the electron microprobe tests results show the distribution of element in healing areas is uniform and the electron microprobe analysis shows the microstructure is mainly fine acicular martensite. The healing effect of deep crack is obvious after the combined treatment. Laser remelting makes the upper crack healing and results in the formation of remelting zone-heat affect zone-matrix structure. At the position near remelting zone, the healing areas formed by the pulse current show a significant columnar crystal structure.
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