变极性TIG焊电弧压力分析

采用压力传感器获取不同条件下的变极性钨极氩弧焊(VPTIG)横焊时的电弧压力,研究分析了电弧压力在径向上的分布规律,对比研究了直流TIG焊、反极性期间占5%,15%的变极性TIG中心电弧压力.结果表明,变极性TIG焊电弧压力的径向分布属于双面指数分布.焊接电流在100~140 A范围内,在电流均值相等的情况下,由于反极性期间电子发射机制和电弧发散等原因,随着一个周期内钨极为正半波的时间比例增加,电弧压力逐渐减小,且焊接电弧积分力与电流的平方近似成正比例关系.

Arc pressure analysis in variable polarity TIG welding

The arc pressure during horizontal variable polarity gas tungsten arc welding(VPTIG) was measured by pressure transducer under different welding conditions. The radial distribution of arc pressure was investigated, and the central arc pressures for DC TIG welding and VPTIG welding with a period of 5% and 15% for direct current electrode positive(DCEP) were compared. The experimental results showed that the radialdistribution of VPTIG pressure was hyperbolic. When the welding current was in the range of 100 A to 140 A and with the same root mean square value, the arc pressure decreased gradually with the increase of time ratio of DCEP at one cycle during DC TIG welding and VPTIG welding with a period of 5% and of 15% for DCEP, due to the difficulties of electron emission and arc divergence in the period of DCEP. And the integrated arc force was directly proportional to the square of welding current.