关键词: 宏微观耦合的黏塑性本构模型;参数识别;参数取值范围;机理法;动态再结晶

Abstract: arameter identification of macro-micro coupled constitutive model is generally taken through inverse analysis. To make the identified result with high confidence degree, the reasonable parameter value domain must be given. Based on the physical mechanism, a procedure is proposed. The procedure can be applied to determine the value domain of the parameter, which is involved in a macro-micro coupled constitutive model considering dynamic recrystallizaton. To improve the robustness of the parameter identification result, some parts of the model is revised and the steady flow stress is described by Tanaka model; a six-step method for the determination of the parameter value domain is given based on the physical mechanism involved in the model; the hot compression deformation of low alloy steel 300M is carried out under different combination of temperature and strain rate, the datum on true stress-strain curve, recrystallized volume fraction, recrystallized grain size, unrecrystallized grain size, maximum grain size difference are obtained, and the steady flow stress in unrecrystallized zone and recrystallized zone is determined, based on the true stress-strain curves. Based on the proposed procedure and the corresponding experimental data, the reasonable parameter ranges are given. The research provides a foundation for parameter identification of macro-micro coupled constitutive model.

Key words: macro-micro coupled viscoplastic constitutive model;parameter identification;parameter value domain;mechanism method;dynamic recrystallization