Welding method for a welded joint in high strength, ferrite type heat resistant steels

摘要

This invention provides a welding method and a welded joint for high strength, temperature resistant steels that produces the same strength as the base metal in the welded joint, thereby resolving the strength problems in the heat affected area by making a simple change to the welding method, and additionally, to extend this advantage to high strength ferrite heat resistant steels by providing a multi-pass buildup welding method for such high strength ferrite heat resistant steels. The multi-layered cap 15a fusion area extends past the heat affected area 13 that lies outside groove 11, and the surface area of the foregoing extension that is required to impart the same level of creep strength as is inherent in the base metal is based on the relationship between the groove width and the base metal thickness shown as hatched area in Figure 1(B).