タイトル(掲載誌)JSME International Journal. Series A, Solid mechanics and material engineering
一般注記A quantitative relation (F-N curve) was obtained betweent the constant impact load due to cavitation bubble collapse and the number of cycles to the incubation period termination. The relation was derived from the linear cumulative damage law, in which all impact loads including those of very low intensity (0.3 N) are assumed to cause damage. The slope of the F-N curve corresponds well with that of the S-N curve for a smooth specimen obtained from a standard fatigue test, provided that the contact area is obtained by the Hertz theory. The incubation period can be evaluated regardless of cavitation test conditions from the cumulative cycle ratio Σ(n_i/N_i), using both the number n_i of impact loads and N_i from an extrapolated F-N curve (modified Miner's law) for the corresponding impact load F_i. Similarly, the F-N' curve was obtained for the steady-state period, where N' was defined as the number of cycles required to achieve a mean depth of penetration (MDP) of 1 micron. The slope of the curve coincides well with that of the S-N curve for a slightly notched specimen. The Σ(n_i/N'_i) has a linear relation with the MDP in the steady-state period. Since N'_i is proportional to 1/F^2_i from the F-N' curve, the cumulative cycle ratio was reduced to ΣF^2_i. ni, which is consistent with the impact energy from the authors' previous report. It is concluded that the ratios Σ(n_i/N_i) and Σ(n_i/N'_i) are suitable parameters for evaluation of the cavitation damage in the incubation and steady-state periods, respectively.
連携機関・データベース国立情報学研究所 : 学術機関リポジトリデータベース(IRDB)(機関リポジトリ)