3604 ナノ-メゾ-マクロ強度解析による疲労特性の解析(S13-1 組織因子,S13 実用構造材料の疲労問題と健全性評価)

概要

論文の詳細を見る
Fully reversed total-axial-strain-controlled low cycle fatigue (LCF) tests have been conducted in air at room temperature on fine- and coarse-grain low-carbon steels, SUS304 steel and SUS316L steel. Three types of hardness measurements, namely nano-indentation, micro-indentation and conventional Vickers hardness tests, with the indentation size ranging from several tens of nm to several tens of μm, were performed for both virgin and fatigued specimens to evaluate the mechanical behaviour at different scales of the cyclically deformed steel during LCF. OM and TEM observation showed that the microstructural parameters are the dislocation cell size, d_<cell>, slip spacing, w_<slip>, and austenitic grain size, d_γ. Referring 10 d_<cell> and 10w_<slip>. Vickers hardness, HV, corresponding to macro strength was expressed as HV=Hv^*_<base>+Hv^*_<sol>+Hv^*_<cell>+Hv^*_<slip>. Hv^*_<base> is the base hardness, Hv^*_<sol> is the solid solution strengthening hardness, and Hv^*_<cell> and Hv^*_<slip> are the fine grain strengthening hardness due to the dislocation cell and slip band.
2006-09-15