Effect of Post Weld Heat Treatment on Mechanical Properties of Hot Wire GTA Welded Joints of SA213 T91 Steel
There is an increasing interest in understanding the processing and properties of Cr-Mo alloy steels. Of these
steels, the modified 9Cr-1Mo steel known as T91/P91 has a wide range of industrial application. During welding this grade
undergoes change in microstructure, increase in hardness and decrease in impact toughness. The present study is concerned
with the comparative study of the effect of post weld heat treatment (temperature and soaking time) on the mechanical
property of hot wire GTA welded SA213 T91 alloy steel tubes. The results of hardness and impact strength measurements
suggest that post weld heat treatment of 2h at 760°C is optimum to re-establish the strength of T91 steel after welding.
Keywords - Hot Wire TIG, modified 9Cr-1Mo steel, post weld heat treatment, toughness