J0406-3-3 Higher Harmonic Imaging and Sizing of IGSCC Appeared in Weld of Ni Based Alloy

Abstract

The sizing of IGSSC in Ni-based alloy weld by the conventional UT technique is very difficult because the backscattered echoes from the coarse grain boundaries often hide the echo from IGSSC. Then, the validity of the higher harmonic imaging technique is demonstrated for detecting and sizing IGSCC in Ni-based alloy weld. The IGSCC was imaged by the normal and oblique incidence techniques. The higher harmonic images of the IGSSC show higher contrast and spatial resolution than those with the conventional UT.