用扫描电镜研究工程塑料的断裂行为

本文研究了工程塑料——聚碳酸酯及聚对苯二甲酸丁二醇酯的微观断裂行为。研究中采用了静载和动载破断实验,用扫描电镜观察断裂形态特征,并结合宏观力学试验过程分析其断裂行为。实验结果表明,热塑性工程塑料,在加载速率及环境温度固定条件下,其微观断裂行为受材料损伤体积空间分布的影响,材料损伤体积宏观空间分布范围宽,则大分子相互协同动作强,应变均匀,微观塑性形变差别小,断口表面趋于平坦;反之,大分子相互协同动作差,应变易于集中,微观塑性形变差异大,断口表面高低起伏大。

Study of the Fracture Behavior on Engineering Plastics by SEM

In the present paper, the micro fracture behavior of two engineering plastics, polycarbonateand polybutylene-terephthalate, have been investigated. The principle method used in the exper-iment was SEM observation of the fracture surfaces which were produced carefully in the slaticload test and the dynamic load test. The fracture behavior was analysed according to the processof macro mechanical test. The results of the experiment indicate that the distribution of damagevolume influences the micro fracture behavior of the engineering plastics at the same loadingrate and constant ambient temperature.