金属材料の応力集中部における超音波特性の変化

抄録

A notched stress concentration part was provided in aluminum alloy A5052 round bar test piece, tensile stress and strain was applied to the bottom. The changing nonlinear acoustic characterization due to strain generated at the bottom of the notch were investigated using Axial-shear-wave EMAT (electromagnetic acoustic resonance), which transmits and receives SH wave propagating in the circumferential direction of a test piece specimen was used. The harmonic components nonlinearity was rapidly increased with tensile stress. The FEM (finite element method) analysis indicates that the increase of strain caused in the stress concentration area corresponds to the change in the harmonic nonlinear. This method may be potentially to capture the microstructural changes in metal materials that occur in the stress concentration area.