%0 Journal Article
%T CRACK TIP DAMAGE AND CRAZING IN POLYMERS UNDER LOADING<br>受载高聚物裂尖的损伤和银纹化
%A Luo Wenbo Yang Tingqing
%A <br>罗文波
%A 杨挺青
%J 力学学报
%D 2003
%I 
%X In situ observation via SEM was conducted to study the crack-tip crazing damage process in polymers under loading. By considering the polymer bulk as linear viscoelastic body and the craze zone at crack tip as a nonlinear damage zone, the control equation for craze zone growth was derived. It is shown that for a time-independent craze-zone stress, the craze zone grows only if the crack-tip stress intensity factor is changed. If the crack-tip stress intensity factor remains constant during loading, the growth rate of the craze zone length will be interrelated to the crack-tip stress, the craze zone length and the rate of change of the craze-zone stress. If both the craze-zone stress and the crack-tip stress intensity factor are time-independent, the craze zone length will be constant during crack growth, which is the case of self-similar crack growth. Moreover, a new stress distribution model in craze zone was presented based on the constructed damage evolution law. The lengthening and thickening of the craze zone at a crack tip was formulated. The numerical calculations from the proposed model agree well with published experimental data.
%K polymer
%K viscoelasticity
%K damage
%K crazing<br>高聚物本体材料
%K 裂尖
%K 损伤
%K 银纹化
%K 原位观测
%K 扫描电子显微镜
%K 材料力学
%K 黏弹性
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=6E709DC38FA1D09A4B578DD0906875B5B44D4D294832BB8E&cid=5D344E2AD54D14F8&jid=4100DA4A1A3BA1B0CE5AD99AE1DFB420&aid=ED52B849C786C193&yid=D43C4A19B2EE3C0A&vid=6209D9E8050195F5&iid=94C357A881DFC066&sid=4AB4178709047BE3&eid=A3F93694B058F76C&journal_id=0459-1879&journal_name=力学学报&referenced_num=2&reference_num=28