8 mm厚T2紫铜功率调制激光-MIG复合焊

目的研究工艺参数与调制参数之间的相互作用对T2紫铜功率调制光纤激光-MIG复合焊过程热效率和稳定性的影响。方法分别设计并进行了平均功率、送丝速度与调制振幅和调制频率的三元二次回归正交试验。其中采用母材熔化区面积表征焊接过程的热效率,采用焊缝中的气孔数量表征焊接过程的稳定性。结果调制振幅约为平均功率的1/3时,母材熔化区面积最大,焊接过程热效率最高,振幅增大或减小都会使熔化区面积减小。平均功率主要决定了焊接过程的线能量,平均功率增大有助于增大母材熔化区面积。送丝速度的大小不仅影响焊接过程的能量输入,而且对熔池的流动行为影响较大。送丝速度过大易使熔池以及小孔失稳,降低焊接过程稳定性,因此送丝速度不宜过大。本研究条件下,10 m/min的送丝速度较为适宜。结论在优化的工艺参数和调制参数下进行功率调制激光-电弧复合焊,可以使8 mm厚紫铜焊接过程的热效率和稳定性同步提升。

Power Modulation Laser-MIG Hybrid Welding Process for 8 mm Thick T2 Pure Copper Plate

This paper aims to research interactive effect between welding parameters and modulation parameters on the thermal efficiency and stability of power modulation fiber laser-MIG hybrid welding for T2 pure copper. The ternary quadratic regression orthogonal tests on average power, wire feed rate, modulation amplitude and modulation frequency were designed and carried out. The melting area of base metal was used to characterize the thermal efficiency during welding, and the number of pores in the weld seam was used to characterize the stability during welding. The results showed that when the modulation amplitude was about 1/3 of the average power, the melting area of the base metal reached the largest, suggesting that the thermal efficiency of the welding process was the highest. The increase or decrease of the amplitude would reduce the melting area of base metal. The average power mainly determined the line energy of the welding process. The increase of average power would lead to the increase of melting area of the base metal. The wire feed rate not only affected the energy input of the welding process, but also had a great influence on the flow behavior of the molten pool. When the wire feed rate was too large, the molten pooland the small holes may be unstable, resulting in the instability of the welding process. Therefore, the wire feed rate should not be too large. In this study, it should be 10 m/min. The results of this paper show that the thermal efficiency and stability of 8 mm thick pure copper welding can be improved simultaneously by power modulation laser-arc hybrid welding with optimized process parameters and modulation parameters.