玻璃态高分子材料银纹力学研究进展

银纹是玻璃态高分子材料所特有的一种现象, 它既是高分子材料的塑性变形和增韧机理, 又 是高分子材料的损伤机理, 还是连接高分子材料微观损伤与宏观破坏的桥梁. 银纹的萌生、 长大与断裂是高分子科学和固体力学所共同关注的难题. 过去几十年在试验、理论和数值模诸方面也取得了显著进展, 但较为系统的理论框架尚未 建立, 人们试图把细观力学的基本知识与高分子系统银纹化现象联系起来的设想才刚刚开始, 且尚未在指导高分子合金设计方面起到关键作用. 本文试图对近10多年来, 高分子银纹化的 研究进展予以介绍和评述. 首先简要介绍银纹的基本形貌、萌生判据与生长规律, 然后分别介绍银纹断裂力学、银 纹损伤力学和银纹细观力学的研究进展和成果, 最后概要介绍银纹分子动力学研究的最新进 展.

Mechanics for crazing in glassy polymers——a review

Crazing is a special phenomenon in glassy polymers. It concerns not only the mechanism of plastic deformation and toughness, but also the damage mechanism of polymers, which is a bridge to link the mi-cromechanism of damage and macroscopic failure of polymers. The initiation, growth and breakdown of craze are open problems for scientists of materials science and solid mechanics. Although extensive researches have be devoted to this topic and considerable advances in the experimental, theoretical and numerical investigations have been made in the past decades, there is still no systematic theoretical framework to describe the crazing of polymers, and people have just started to link the fundamental knowledge of micromechanics to the phenomenon of crazing of polymers, and this kind of studies have not yet played a key role in guiding the blend design. In this paper, we introduce the advances in polymer crazing in the past decade. A brief introduction to the structure, the initiation criterion, the growth and the breakdown of crazing is presented first. Emphasis of the paper is on the recent advances of the applications of fracture mechanics, damage mechanics, micromechanics and molecular dynamics in the studies on the crazing of glassy polymers.