203 ダイナミック硬さ試験による応力分布測定法の開発

抄録

Development of a non-destructive testing method for measuring stress distribution is one of the major research items from a viewpoint of structural integrity. A dynamic hardness testing was examined to clarify the applicability of the stress distribution measurement in graphite components. The dynamic hardness was measured using pre-stressed graphite specimens with stress profile from tension to compression. Simultaneously, a FEM analysis was performed to evaluate the sensitivity of dynamic hardness with stress distribution. In the analysis, materials non-linearity, namely elastic-plastic stress behavior, was considered applying in surface element. Therefore, the applicability of the dynamic hardness testing was clarified from both experimental and analytical results. From both analytical and experimental studies, dynamic hardness decreased with increasing tensile pre-stressed specimens, on the other hand, it increased with increasing compressive pre-stressed specimens.