2 0 0 0 OA 連続体損傷力学に基づくディーゼル機関用シリンダヘッドのクリープ疲労寿命解析
- 著者
- 岡 正徳 都井 裕
- 出版者
- 一般社団法人 日本機械学会
- 雑誌
- 日本機械学会論文集A編 (ISSN:18848338)
- 巻号頁・発行日
- vol.79, no.806, pp.1411-1421, 2013 (Released:2013-10-25)
- 参考文献数
- 18
- 被引用文献数
- 1 1
The elasto-viscoplastic-creep constitutive equation based on the concept of continuum damage mechanics is formulated for the gray cast iron as used in diesel engine parts. It employs the viscoplastic strain given by Chaboche-Rousselier and the creep strain given by Perrin and Hayhurst. A part of the material parameters contained in the creep constitutive equation which was previously identified by Oka and Toi are assumed to be temperature-dependent in the present study. The identified model is applied to the creep fatigue life prediction of the cylinder head used in diesel engine parts which is made of gray cast iron. Although there are some points to be improved, the validity of the proposed model is illustrated by comparing the calculated results with the experimental results for the crack initiation locations and the crack propagation directions.
1 0 0 0 OA 完全陰的応力更新による拡張下負荷面モデルに基づく弾塑性解析
- 著者
- 安食 拓哉 岡 正徳 橋口 公一
- 出版者
- 一般社団法人 日本機械学会
- 雑誌
- 日本機械学会論文集 (ISSN:21879761)
- 巻号頁・発行日
- vol.82, no.839, pp.16-00029, 2016 (Released:2016-07-25)
- 参考文献数
- 22
- 被引用文献数
- 4 6
Elastoplastic analysis of solid structures under cyclic loadings is increasingly required in recent years. To this end, it is necessary to adopt elastoplastic model capable of describing cyclic loading behavior and to employ stress integration algorithm that enables effective and robust calculation. The subloading surface model excluding a purely-elastic domain is capable of describing the cyclic loading behavior in addition to the monotonic loading behavior. The complete implicit stress-update algorithm by return-mapping based on the closest-point projection for the extended subloading surface model is formulated in this article. In addition, the consistent tangent modulus tensor required for the accurate calculation by the return-mapping is formulated in the inverse matrix form. They are implemented into the implicit finite element program through the user-subroutine. We simulate elastoplastic behavior of metals to assess calculation accuracy and efficiency of the proposed algorithm. Numerical experiments for cyclic loading behavior of metals are shown in order to verify the accuracy and the efficiency of the computer program based on the return-mapping and the consistent tangent modulus tensor.