1060Al高频微振激光焊接接头气孔及组织

采用激光和高频微振相耦合的方法焊接5 mm厚的1060Al,研究振动对焊缝成形、气孔尺寸、数量和分布、显微组织及显微硬度的影响规律,并研究了熔池的流动状态对气孔位置分布的影响. 结果表明,当其它激光工艺参数一定,振动频率为1 173 Hz时,组织晶粒细化最为明显,焊缝宏观成形较好,焊接接头可获得最佳表面外观,焊缝中心平均显微硬度从无振动条件下的27.2 HV增加到有振动条件下的29.4 HV,提高8.1%. 振动频率为923 Hz时,气孔能够有效地得到抑制. 振动影响熔池的流动与激光匙孔的稳定性,与焊缝气孔形成具有一定的相关性,表现在气孔逐渐向焊缝表面逸出.

Porosity and microstructure characteristic of 1060Al laser welded joint under high frequency micro-vibration condition

The 5 mm thick 1060Al was welded by the coupling of laser and high-frequency vibration. Vibration effect on welding formation, size, quantity and distribution of porosities, microstructure and microhardness of the joint were researched. The influence of the flow of the molten pool on the hole position distribution was also studied. The results showed that the best welding formation could be got with 1 173 Hz vibration frequency. The grain refinement was the most obvious. The best surface appearance could be obtained. The average value of welding zone microhardness increased from 27.2 HV without vibration to 29.4 HV with vibration, which increased by 8.1%. Under the condition that vibration frequency was 923 Hz, the porosities were effectively suppressed. The flow of the molten pool and the stability of laser keyhole were influenced by frequency of micro-vibration which had certain relevance with the welding porosity formation. The pores were gradually gathered to the welding surface with frequency of vibration increasing.