学术
织构可调塑性本构模型标定及其应用
陈贻平[1,2,3] 李荣彬[3] 杜雪[3]
[1]华中科技大学土木工程与力学学院,武汉430074 [2]华中科技大学材料成形与模具技术国家重点实验室,武汉430074 [3]香港理工大学工业及系统工程学系,香港红坳
摘 要:
提出了利用率相关晶体塑性模型标定织相可调本构模型的求解步骤，得出了一组依赖于晶粒间相互作用假设而独立于具体板材织构的本构相关系数.以此为基础再结合板材织构系数所得出的本构模型系数可避免出现屈服面非外凸的情形.利用所提求解步骤对在不同热处理条件下产生不同织构的AL5052铝合金板的深拉成形过程进行了有限元模拟.结果再现了典型织构在板材成形过程中所出现的塑性各向异性，从而表明求解步骤的可行性.[著者文摘]
文章出处:
《固体力学学报》-2007年28卷3期 -241-248页
分 类 号:
CALIBRATION OF TEXTURE-ADJUSTABLE STRAIN-RATE POTENTIAL AND ITS APPLICATION
Chen Yiping, Li Rongbin, Du Xue （1. School of Civil Engineering and Mechanics, Huahong University of Science and Technology , Wuhan ,430074;2. State Key Laboratory for Forming Simulation and Die and Mould Technology, HUST,Wuhan ,430074;3. Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hung Horn, Kowloon, Hong Kong, China）
Abstract:
An accurate prediction of plastic anisotropy induced by initial texture in sheet metal forming operations depends on the constitutive models adopted. Models of engineering interest include both phenomenological formulation and crystal plasticity based on dislocation slip. In addition to the above two approaches that are commonly adopted in FE analysis, an alternative is available, which describes anisotropic behavior of polycrystalline sheet metals by an analytic yield function to keep the computing time as low as possible and also takes explicitly into account the crystallographic texture of the material to give a more precise description of plasticity anisotropy. However, the locus of such a yielding potential based on the rate-independent crystal plasticity may exhibit an unrealistic concave shape, which will make it impossible to obtain a convergent solution. To circumvent the difficulty, a detailed computation procedure is presented to calculate the constitutive coefficients based on rate-dependent crystal plasticity. The combination of the coefficients obtained with experimentally measured texture coefficients of an annealed FCC polycrystalline sheet metal will provide a complete constitutive characterization of the material. As an application of the calibrated model, the process of deep drawing by hemispherical punch is simulated, in which plastic anisotropy（earring） corresponding to typical texture type is observed , thus demonstrating the applicability of the coefficients found.[著者文摘]
Key words:
constitutive model, texture, FEM
基金资助:
教育部留学回国人员科研启动基金及华中科技大学材料成形与模具技术国家重点实验室基金资助.
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