Measurement of residual stress on a unidirectional solidified AlO/YAG eutectic composite using synchrotron and neutron diffraction

Suzuki, Hiroshi  ; Waku, Yoshiharu*; Nakagawa, Narihito*; Akita, Koichi*; Moriai, Atsushi; Morii, Yukio

The residual stress in only YAG phase was measured on the surface of the AlO-YAlO(YAG) eutectic composite(AlO/YAG MGC) using the low energy synchrotron X-rays. The residual stresses in plane stress condition were significantly different between top and side surfaces of the specimen. Therefore, an anisotropic triaxial residual stress probably exists within the MGC. The residual stress within the MGC was also measured using a neutron diffraction. The residual stress in the YAG phase rose from compression in the solidification direction to tension in perpendicular direction. The residual stress in the AlO phase was anisotropic compression and there was no tension in all directions. This anisotropic residual stress could be explained by the crystallographic anisotropy of thermal expansion in the AlO phase. However, both phase stresses were not balanced, so that it is expected that there would be the stress distribution in MGC sample used in this study.