A finite strain elasto‐plastic material model incorporating kinematic and isotropic hardening for thermoplastic polymers
A finite strain elasto‐plastic material model incorporating kinematic and isotropic hardening for thermoplastic polymers
复制标题
结合了热塑性聚合物的运动学和各向同性硬化的有限应变弹塑性材料模型
DOI：
10.1002/pamm.201800233
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Felder
中科院分区：
文献类型：
--
作者：
Felder
半结晶热塑性聚合物具有上级机械性能，因此在许多技术相关应用中非常重要。在由热塑性聚合物制成的部件的热成型过程中，“回弹效应”，即部件在从工具卸载和移除之后的不期望的变形，描述了一个主要问题。由于残余应力的形成而发生这些形状变形。为了抵消这种影响，通常会进行耗时且成本密集的试错法，以仔细确定最佳工艺参数集。因此，对准确预测零件在成形过程中的材料和结构响应的计算模型提出了强烈的需求。因此，本文提出了一种适用于等温过程中大变形和大变形率的唯象模型公式。为了捕获聚合物的双相性质，即为了解释底层微结构的无定形和半结晶区域，应用两相的平行排列。通过混合规则获得总体材料响应。的超弹性，粘塑性材料模型的定性验证显示了有前途的潜力，预测热塑性聚合物的成型过程中的残余应力的形成和松弛。
Semicrystalline thermoplastic polymers have superior mechanical properties and are thus very important in numerous technically relevant applications. During the thermoforming process of parts made of thermoplastic polymers the “springback effect”, i.e. the undesired distortion of a part after unloading and removal from tooling, depicts a major problem. These shape distortions occur due to the formation of residual stresses. To counteract this effect, time‐consuming and cost‐intensive trial and error approaches are typically conducted to carefully determine the optimal set of process parameters. Hence, a strong demand for computational models, which accurately predict the material and structural response of the part during forming, arises. Therefore, a phenomenological model formulation is proposed in this work, which is valid for large deformations and large deformation rates in the context of isothermal processes. To capture the biphasic nature of the polymer, i.e. to account for the amorphous and semicrystalline regions of the underlying microstructure, a parallel arrangement of both phases is applied. The overall material response is obtained by a rule of mixture. The qualitative validation of the hyperelastic, viscoplastic material model shows the promising potential to predict the formation and relaxation of residual stresses during the forming process of thermoplastic polymers.
影响因子：
9.8
作者：
T. Brepols;I. Vladimirov;S. Reese
通讯作者：
T. Brepols;I. Vladimirov;S. Reese