【摘要】 本文研究了用方波交流焊接电源焊接AI—Cu—Mn系(147)高强度铝合金,改善接头性能的结果。改变正负半波电流比值β,可以改变阴极清理区大小及焊缝成形,实验结果表明,当β=0.7时,焊接(147)高强度铝合金,接头强度可以比一股正弦波提高10％以上。这是由于改变了对母材的热输入量,造成焊缝热影响区减小,焊缝及熔合线组织细化,减少气孔等造成的。更多还原

【Abstract】 Application of AC TIG Welding with square-wave to the high-strength Al-Cu-Mn alloy system(147) and an improvement in mechanical behaviours of the weld joint were studied.It was found that the cleaning region and the formation of a welding seam can be controlled by changing the amplitude ratio β of positive current to negative current. Experimental results showed that when β=0.7, the strength of a joint by square-wave AC TIG welding will increase by a factor of 1/10-more than that by ordinary sinusoidal TIG welding This gives rise to controlling of the heat input narrowing of the heat-affected zone, refining of the metallurgical structure of weld junction and lowering of the porosity in the weld Joint.更多还原