Abstract
Behavior of displacement at welded joints during welding is an important factor for reliability of the joints. But in-situ measurement of the behavior is very difficult because contact method such as strain gauge is inapplicable in high temperature. In this study, ESPI (Electronic speckle pattern interferometry) system is applied to in-situ measurement of displacement increment distribution in SUS304 steel, 9%Ni steel, and low transformation temperature welding (LTTW) material during GTA welding. Qualitative tendency of measured results agrees with numerical simulation. Expansion behavior of phase-transformation is detected in 9%Ni steel and LTTW material during cooling. Moreover ESPI system enabled measurement of displacement increment at uranami bead surface and surrounding area of molten pool. These results show that ESPI system is applicable to measurement of displacement distribution at welded joints during welding process.
