1977 年 46 巻 1 号 p. 1011-1016
For TIG and MIG arc welding, shielding gases such as Ar, He and CO2 are widely used to protect the weld parts from the surrounding air.
Up to now, the optical method known as the Schrieren method, gas chromatography and the thermistor technique have been used to observe the shielding gas flow pattern. However, these methods are limited to examining the static state no arcing condition.
We have developed an experimental method to make the actual gas flow pattern during arcing visible using a laser light source, and have found that the shielding gas distribution around the arc changed remarkably with an increase in current, arc length, gas flow rate, etc. when compared with the no arcing state.