碳酸钙增强聚丙烯复合材料的断裂韧性

介绍了J积分方法的概念、理论和方法,并应用参考国外文献建立的,积分测试方法,结合扫描电镜形态分析研究了碳酸钙增强聚丙烯复合材料的断裂韧性。结果表明,碳酸钙的加入使复合材料对裂纹起始和增长过程的阻力都有大幅度提高,聚丙烯基体发生较大幅度塑性形变屈服后取向牵伸吸收塑性能。刚性填料加入时所导致的基体应力集中及界面脱粘后的基体应力集中促进聚丙烯基体产生局部区域微观塑性牵伸被认为是断裂韧性提高的原因。

THE FRACTURE TOUGHNESS CaCO_3 REINFORCED POLYPROPYLENE COMPOSITE

J-integral method is based on the concepts of postyield fracture mechanics. The concept, theory of J-integral method and it' s usage to characterize the fracture toughness of calcium carbonate (CaCO3) reinforced polypropylene composite are described. The crack initiation and propagation resistances both increase with CaCO3 addition.Large scale plastic deformation was observed for polypropylene matrix. Combined with fracture surface morphology analysis via SEM,it is concluded that stress concentrations around rigid inorganic filler particles both before and after interface debonding promote a kind of local plasticity , and microdrawing of PP matrix, which are the reason of fracture toughness increase.