Reliability improvement for neutron stress measurement of weld joint

Suzuki, Hiroshi  ; Akita, Koichi

It has been known to be difficult to measure the residual stress near a weld accurately due to a complex microstructure in a heat affected zone. In this study, we show that the residual stress around the weld can be measured accurately in consideration of the influences of phase transformation and intergranular strains. Furthermore, it is shown that a change in residual stress due to crack propagation near the weld can be measured by the neutron diffraction technique. The neutron diffraction technique can be a complementary measurement technique with a mechanical measurement technique like strain gauges, as an important method to measure residual stresses of welded structures.