摘要
基于热力学相容的本构模型并合理地定义广义时间，得到了描述蠕变、塑性及其交互作用的统一型本构方程。进而通过对在蠕变—塑性交互作用过程中材料内部子结构及其变化的分析，将材料的强化分解为对应于非弹性应变范围的强化和由蠕变变形导致的附加强化。对高温环境二维应力路径下３０４不锈钢的蠕变—塑性交互作用过程进行了分析，取得了与Ｏｈａｓｈｉ等的实验相吻合的结果。
A thermomechanically based unified constitutive model is proposed for coupled creep and plasticity, which encompasses pure plastic and creep deformation as its special cases, respectively. In this model, both creep and plastic deformations are considered as the irreversible deformation activated in thermodynamical process, and a generalized time is employed, which is defined in terms of the history of inelastic strain and real time. The different hardening mechanisms in coupled creep and plasticity process are taken into account by a hardening function consisting of two hardening factors f l and f c. The proposed model is applied to the analysis of the coupled reversed creep and cyclic plastic behavior of 304 stainless steel subjected to uniaxial and biaxial loading at elevated temperature. The validity of the model is verified by the comparison between the calculated and experimental results.
出处
《应用力学学报》
CAS
CSCD
北大核心
1997年第3期110-114,共5页
Chinese Journal of Applied Mechanics
关键词
蠕变
塑性
本构方程
验证
高温材料
creep, plasticity, constitutive relation, verification.
