The Signal Examination in Variable Polarity Plasmaarc Welding of Aluminum Alloy

In this thesis, the signal examination system in variable polarity plasma arc welding of aluminum alloy based on industrial computer was created. The characteristic signal in process of variable polarity plasma arc welding was examined. Mechanics characteristic and electricity characteristic of variable polarity plasma arc was analyzed and showed that they were better function than free arc in arc force and arc electrode et al. The result had important guide-meaning in stability of variable polarity plasma arc welding and the control of welding process.