权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

A Study on the Application of Inelastic Constitutive Relations under Plasticity-Creep Interaction and the Evaluation of Life Prediction Methods

塑性-蠕变相互作用下非弹性本构关系的应用研究及寿命预测方法评价

基本信息

批准号：
01302026
负责人：
INOUE Tatsuo
金额：
$ 7.1万
依托单位：
Kyoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Co-operative Research (A)
财政年份：
1989
资助国家：
日本
起止时间：
1989 至 1990
项目状态：
已结题

项目摘要

The first Part of this report covers the extension of the second phase project, and presents more developed results on the applicability of the constitutive models and life prediction methods, respectively, to the multiaxial stress state of combined tension-compression and cyclic torsion. The results of analysis were compared with the experimental data.The motivation of the second part concern the third phase of the project which arises from engineering requirement that the schemes are to be used for practical design purposes : Applicability of the inelastic constitutive models to finite element calculation is examined by comparing the analytical stress/strain response near notch root of the bar with experimental results, and fatigue-creep lives of the specimen are evaluated by applying the life prediction methods.Four loading patterns such as creep loading, fast-fast and slow-slow cyclic straining and fast-fast cyclic straining with a tension hold-time were applied to the specimen. The results of analysis of stress/strain simulation were compared with measured strain at notch root by means of "Strain-Pecker", a capacitance type extensometer for high temperature use. The predicted crack initiation Life was also confirmed by the experimental lives which were detected by a direct current potential drop technique, and failure life was defined as the cycles of 25% stress drop from saturation.

本报告的第一部分涵盖了第二阶段项目的扩展，并分别介绍了本构模型和寿命预测方法对拉压和循环扭转组合多轴应力状态的适用性的更多进展结果。将分析结果与实验数据进行比较。第二部分的动机涉及该项目的第三阶段，该项目源于工程要求，即这些方案用于实际设计目的：通过将杆件缺口根部附近的分析应力/应变响应与实验结果进行比较，检验非弹性本构模型在有限元计算中的适用性，并通过应用寿命预测来评估试件的疲劳蠕变寿命。对试样施加蠕变加载、快-快和慢-慢循环应变以及快-快循环应变和拉力保持时间等四种加载模式。将应力/应变模拟分析结果与使用高温用电容式引伸计“Strain-Pecker”测量的缺口根部应变进行比较。预测的裂纹萌生寿命也通过直流电势降技术检测的实验寿命得到证实，失效寿命定义为从饱和应力下降25%的循环次数。