摘要
采用不同的冷却方式研究冷却速率对聚乙烯管材专用料力学性能的影响,发现随冷却速率减小,其屈服强度增大,冲击强度先升高后降低,空气冷却时最高,最大差值达12 kJ/m2。通过扫描电子显微镜、热分析、热台偏光及密度法对韧性提高的机理进行了研究,发现PE100管材料在塑性形变中产生的银纹化与其晶片厚度和结晶度相关,空气冷却时,晶片较厚,晶片数目较多,塑性形变中产生空隙较多,冲击断面中形成的银纹较致密,吸收的能量更多,裂纹更难扩展。
The influence of cooling rates on mechanical property of PE100 pipe material prepared by different cooling ways was studied. It is found that with cooling rates decreasing, the yield strength decreases, the impact strength increases at first, then fell, the maximum is reached by air cooling. The toughening mechanism was studied by SEM, DSC and density method, it is found that craze effect of PE100 pipe material in plastic deformation process was relative with the thickness of crystallite and crystallinity, by air cooling, the crystallite is thicker, the number of crystallite is larger, so the formed cavities during plastic deformation process is more remarkable, and the formed craze in the fracture surfaces is denser, therefore, the toughness of PE100 is enhanced.
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
2008年第6期83-87,共5页
Polymer Materials Science & Engineering
基金
国家重大基础研究计划(973计划)项目(2005CB623808)