PURPOSE: To improve the creep characteristic and the bending performance of a different material joint by welding a different kind base material by a co-metal or a welding material of an intermediate composition, remelting repeatedly a junction boundary part by shifting a phase, and forming one or more intermediate composition areas between base materials.
CONSTITUTION: Different kinds of base materials A, B are welded by a co-metal A', and thereafter, a junction boundary part is remelted by a necessary heat source, and the intermediate composition area a1 of the co-metal A' and the base material B is formed by a dilution. Subsequently, the boundary part between the area a1 and the base material B is remelted, and also an intermediate composition area a2 is formed, and a different material boundary part is remelted repeatedly by shifting successively the phase. In this way, for instance, the concentration differences ΔE1, ΔE2... of the quantity of Cr in each boundary part of a different material joint are reduced. In this way, the creep characteristic and the bending performance of the different material joint are improved.
KOBAYASHI TOSHIRO
HATAKEYAMA HISASHI
