Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : September 03, 2017 - September 06, 2017
Thermal shock fracture behavior of alumina ceramics was characterized using Disc-on-Rod (DoR) test. The thermal stress distribution was calculated by FEM analysis from the temperature distribution measured using IR camera. And microfracture process was evaluated by acoustic emission (AE) technique. Using elliptical specimen and elliptical rod, unbalanced biaxial stress state was obtained. Specimen size and shape were determined by FEM analysis simulating DoR test. As the result, the contact between specimen and rod was nonuniform. Consequently maximum stress occurred at the point that is different from the center. Fracture initiated from the maximum stress point. And crack initiated perpendicularly to the first principal stress direction at the maximum stress point. Stress ratio at the specimen center is controlled approximate target stress ratio value. Finally, thermal shock fracture behavior could be evaluated under unbalanced biaxial thermal stress.
