Results of tensile, hardness and bend tests of modified 9Cr 1Mo steel welds: Comparison between cold wire and hot wire gas tungsten arc welding (GTAW) processes

摘要

Hot wire Gas Tungsten Arc Welding (GTAW) process is considered in addition to conventional cold wire GTAW process for the manufacture of Steam Generators (SG) for India's Prototype Fast Breeder Reactor (PFBR). During manufacture, it is an obligatory requirement to weld one test coupon for every 20 m of weld length on the actual SG for ascertaining the properties during fabrication. Weld pads thus prepared were used for characterization of hardness, bend and tensile properties of modified 9Cr 1Mo steel welds produced by hot wire and cold wire GTAW processes and the test results were compared. The results revealed that hardness, bend and tensile properties of modified 9Cr 1Mo steel welds of hot wire and cold wire GTAW processes are similar and no genuine difference exist between these two welding processes. Further, the advantage of high quality with excellent weld profile and high productivity has been realized using hot wire GTAW process.