Effect of Wire Feeding Conditions on Grain Refinement in Weld Metal of Type 310S Stainless Steel

- Grain Refinement in Weld Metal by Hot-wire GTAW Process -

Abstract

The aim of this study was to investigate the influence of wire feeding conditions such as wire feeding position and power supply distance on the fine grain formation in weld metal of type 310S stainless steel. When the wire feeding position was far from electrode of GTAW, area ratio of fine grain in weld metal increased. The maximum area ratio was obtained when the filler wire was fed to the back of weld pool and the wire melting depended on the joule heating. When the power supply distance was short, the wire wasn't fed to the back of weld pool. On the other hands, when the power supply distance was long, the wire wasn't also fed to the back of weld pool. Because, this phenomenon was related to the local melting region in the wire corresponding to the temperature gradient of wire. Therefore, the adequate feeding conditions was required to form the fine grain by hot-wire GTAW process.