利用4 kW光纤激光，对1.5 mm厚TC4钛合金板试件进行了激光对接焊试验。在对接试件中间夹入0.08 mm厚铝箔，通过调整工艺参数获得最佳焊缝成形。对比研究了加铝箔前后焊接接头的成形、金相组织、拉伸性能及显微硬度。结果表明，在TC4钛合金试件中添加铝箔中间夹层，能获得成形更好、拉伸强度更高的焊接接头；TC4钛合金/铝箔焊缝区显微硬度要明显高于未添加铝箔的焊缝区，两者相差近90 kg/mm2； TC4钛合金/铝箔焊缝区晶粒更加细小，针状α′相组织细小，且呈现网篮状组织分布特征；两种焊接接头热影响区的显微硬度和显微组织差别不大。

Butt welding experiments on 1.5 mm thick TC4 titanium specimen are conducted by using 4 kW fiber laser. The specimen is jointed 0.08 mm aluminum foil in the intermediate layer. The optimal weld shape can be attained by adjusting craft parameters. The shape, metallographic structure, tensile properties and microhardness on welding joint are discussed. It is shown that better welding joint and stronger tensile strength can be achieved by adding aluminum foil in the intermediate layer of TC4 titanium specimen. Microhardness is dramatically stronger in the weld pool with TC4 titanium and aluminum foil than that in the weld pool with only TC4 titanium. The difference is about 90 kg/mm2. In the weld pool with TC4 titanium and aluminum foil, grain is much smaller, and the acicular α′ structure is tiny, and the metallographic structure is in net distribution. Besides, the two kinds of welding joints in the heat-affected zone have almost the same microhardness and microstructure.