温度对HDPE断裂形态与冲击韧性的影响

Effect of Temperature on the Fracture Morphology and Impact Toughness of HDPE

通过对不同温度条件下HDPE简支梁缺口冲击过程中的冲击力-位移曲线的分析、冲击强度的测试以及试样断面形态特征的SEM观察分析,发现室温时冲击断面的银纹质剪切唇区较大,温度在-35^-10℃区间冲击断面呈现平坦带和粗糙带交替相间的抛物线形貌区特征;剪切唇对应于韧性断裂,抛物线形貌区中的无屈服形变的粗糙带对应于脆性解理。

In this paper notched chapy impact strength and impact force-displacement curves of HDPE were measured and analysed at different temperatures. Also the SEM observation of fracture surface morphologies of HDPE specimens, which were impacted at different temperatures, were analysed. It reveals that there is a large crazed shear lips region at room temperature and the parapola morphology regions of smooth and corase strips alternate on the impact fracture surface of HDPE at the temperature between -35 and -10℃. The shear lips region indicates toughness fracture, but the corase strips without yielding deformation in the parapela morphology region exhibit a brittle cleavage.