Abstract
The inverter controlled CO2 gas shielded arc welder was developed, which contained micro-computer for controlling the current and voltage waveforms. The values of current and voltage can be shifted to any level ai any time during short circuit duration and/or arc duration.
For the purpose of controlling the waveforms, a time period which contains a short circuit duration and an arc duration is divided into 6 stages, and also 14 factors of the waveforms which concern with current, voltage and time were selected.
The waveform factors concern with the behavior of droplet at the primary stage in short circuit duration and at the later stage in arc duration had remarkable effect on sticking spatter in CO2 gas shielded arc welding.
Using the new waveform control method, spatter in CO2 gas shielded arc welding decreased. Compared with the conventional method with thyristor controlled power sourse, sticking spatter on the nozzle and on the base metal by new method decreased to 1/5 and 1/50 respectively.
