采用10 kW碟片激光器焊接5 mm厚的TC4钛合金, 研究了焊接参数变化对焊接接头成形的影响。实验结果表明, 在碟片激光深熔焊条件下, 离焦量的改变对焊缝成形影响较大, 焊接速度变化对焊缝成形影响较小。在不同的焊接参数下, TC4钛合金焊缝具有近“酒杯”形和近“X”形两种截面形貌。不同的焊接参数下对焊缝熔宽尺寸影响较大, 当P＝4.3 kW, v＝2.7 m/min, f＝-2 mm时可以得到最窄的熔宽, 当P＝4.3 kW, v＝2.1 m/min, f＝0 mm时可以得到较宽的熔宽。随着焊接参数的变化, 激光的热输入也随之改变, 受高温等离子体和金属蒸汽的影响, 熔宽尺寸随之改变。通过调整激光功率、焊接速度和离焦量等激光焊工艺参数,可以对焊缝成形进行有效控制, 提高焊接接头质量。

Butt welding experiments on 5 mm thick TC4 titanium alloy are conducted by using a 10 kW disc laser. The effects of welding parameters changes on the formation of welded joints are studied. The experimental results show that under the condition of disc laser deep penetration welding, the change of defocusing amount has a great influence on weld forming. The change of welding speed has little effect on weld forming. TC4 titanium alloy weld has a nearly "wine cup" shape and near "X" shape two cross-section morphologies. Different welding parameters have a great influence on weld width. The narrowest weld width can be obtained when P＝4.3 kW, v＝2.7 m/min, f＝-2 mm. A wider weld width can be obtained when P＝4.3 kW, v＝2.1 m/min, f＝0 mm. With the change of welding parameters, the heat input of laser also changes, and the size of melt width changes with the influence of high temperature plasma and metal vapor. By adjusting the laser welding process parameters such as laser power, welding speed and defocus amount, can effectively control the weld formation and improve the quality of the welded joints.