非消耗電極式アーク溶接におけるステンレス鋼溶接金属の窒素吸収について

抄録

Using an arc atmosphere controlling chamber, effects of the welding conditions and atmosphere on the nitrogen content of the stainless steel weld metal by gas tungsten arc welding were investigated in comparison with those on the iron weld metal. The results are as follows:
(1) The temperatures of stainless steel and iron molten pools were measured as about 1530°C and 1630°C, respectively.
(2) The nitrogen content of stainless steel weld metal decreased with increasing the welding current, as well as that of iron weld metal.
(3) The nitrogen content of stainless steel weld metal hardly depended on the arc length, as well as that of iron weld metal.
(4) The nitrogen content of stainless steel weld metal increased with increasing the travel speed, while that of iron weld metal hardly depended on the travel speed.
(5) The nitrogen content of stainless steel weld metal increased with the nitrogen partial pressure at low nitrogen partial pressure region, and was constant at the nitrogen partial pressure region above 0.2 atm in N₂-Ar gas mixture atmosphere, as well as that of iron weld metal.
(6) The nitrogen absorption by stainless steel weld metal was discussed with equilibrium data.