交流TIG电弧粉末堆焊层成形特点的研究

Formation characteristics of AC TIG arc powder surfacing layer

为了降低TIG电弧堆焊时因直流正接造成堆焊金属稀释率过大的问题,尝试使用交流TIG电弧进行粉末堆焊,研究了堆焊层的成形特点。实验表明,与直流正接相比,使用相同电流值的交流TIG电弧进行粉末堆焊,获得的堆焊层熔宽更大,熔深和母材熔化量更小,因而具有更小的深宽比和稀释率。这一规律不随堆焊电流的大小和堆焊材料的不同而发生变化。

The commonly used direct current（DC） straight polarity of TIG art. causes large dilution of surfacing metal in surfacing process. TIG arc of alternative current polarity is introduced and the shape parameters of the surfacing layers are studied.The results show that the AC-are-prepared layers have larger weld widths.smaller weld depths and melting amounts of hase metal.therefore lower aspect ratios and dilutions are observed than in the ease of layers prepared by DC straight arc with the same current.This result is sustainable no matter how high the current is and what powder is preplaced.