Studies on the growth of voids in amorphous glassy polymers
Studies on the growth of voids in amorphous glassy polymers
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非晶态玻璃态聚合物中孔隙生长的研究
DOI：
10.1023/a:1004356108870
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发表时间：
1998
影响因子：
4.5
通讯作者：
P. D Wu
中科院分区：
文献类型：
--
作者：
A. Steenbrink;E. van der Giessen;P. D Wu
对非晶态玻璃聚合物中孔洞周围的局部变形进行了数值研究。这个问题与聚合物-橡胶共混物有关，一旦橡胶颗粒内部发生空化。这些研究基于轴对称或平面细胞模型的详细有限元分析，具有大的局部应变和描述随时间变化的屈服的最新材料模型，随后是由于分子取向的固有软化和随后的应变硬化。结果表明，孔洞周围的塑性是由两种剪切带的组合产生的，我们分别称之为翼形和狗耳形剪切带。在取向硬化的驱动下，剪切带的扩展导致了空洞的扩展。还讨论了在生长过程中，考虑到可能的开裂，孔洞之间的局部静水应力分布的演变。©1998 Kluwer学术出版社
Numerical studies are presented of the localized deformations around voids in amorphous glassy polymers. This problem is relevant for polymer–rubber blends once cavitation has taken place inside the rubber particles. The studies are based on detailed finite element analyses of axisymmetric or planar cell models, featuring large local strains and recent material models that describe time-dependent yield, followed by intrinsic softening and subsequent strain hardening due to molecular orientation. The results show that plasticity around the void occurs by a combination of two types of shear bands, which we refer to as wing and dog-ear bands, respectively. Growth of the void occurs by propagation of the shear bands, which is driven by orientational hardening. Also discussed is the evolution of the local hydrostatic stress distribution between voids during growth, in view of possible craze initiation. © 1998 Kluwer Academic Publishers