Equivalent plastic strain gradient crystal plasticity – Enhanced power law subroutine
Equivalent plastic strain gradient crystal plasticity – Enhanced power law subroutine
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等效塑性应变梯度晶体塑性 – 增强幂律子程序
DOI：
10.1002/gamm.201310008
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发表时间：
2013
期刊：
影响因子：
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通讯作者：
T. Böhlke
中科院分区：
文献类型：
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作者：
S. Wulfinghoff;T. Böhlke
提出了基于等效塑性应变梯度的缺陷能梯度晶体塑性理论。与其他梯度晶体塑性理论类似，梯度硬化理论保留了单晶滑移的运动学特性，建立了位错长期相互作用的模型，并在流动规律中加入了反应力项。由于减少了四个节点自由度，有限元实现可以处理由更多颗粒组成的系统（与其他理论相比），而无需精心设计或昂贵的计算机系统。重点对幂律材料子程序进行了改进。基于改进的牛顿格式的起始值，对相关的隐式欧拉格式进行了优化。三维模拟表明，与标准牛顿方案相比，所提出的算法可以实现更大的时间步长。（©2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim）
A gradient crystal plasticity theory is presented including a defect energy based on the gradient of an equivalent plastic strain measure. Preserving the single crystal slip kinematics, the gradient hardening contribution models dislocation long range interactions adding a back‐stress term to the flow rule, similar to other gradient crystal plasticity theories. Owing to a reduced number of four nodal degrees of freedom the finite element implementation can handle systems consisting of an increased number of grains (compared to other theories) without elaborate or costly computer systems. Emphasis is put on the enhancement of the power law material subroutine. The associated implicit Euler scheme is optimized based on an improved starting value for the Newton scheme. Three‐dimensional simulations illustrate that the proposed algorithm facilitates significantly larger time steps compared to the standard Newton scheme. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)