试样厚度对共聚聚烯烃材料断裂行为参数的影响  

Specimen Thickness Dependence of Fracture Parameters of a Co-Polypropylene

作　　者：谢邦互[1] 郑爱舞[1] 李忠明[1] 杨伟[1] 杨鸣波[1] 

机构地区：[1]四川大学高分子科学与工程学院,高分子材料工程国家重点实验室,四川成都610065

出　　处：《高分子材料科学与工程》2007年第1期185-188,共4页Polymer Materials Science & Engineering

基　　金：中石化基础研究项目(X504004);国家自然科学基金(50373027)资助

摘　　要：采用基本断裂功法对共聚聚丙烯压制双边缺口拉伸试样的断裂行为进行研究,分析了厚度变化对材料多项断裂参数的影响。结果表明,当厚度在0.6 mm^1.1 mm时,材料的断裂韧性we随厚度增大呈现出明显的下降趋势,下降幅度约30%,主要由屈服后的we,n降低所致,屈服前的we,y无明显变化;材料的比塑性功βwp随厚度增大未呈现明显的变化,且屈服前的βywp,y和屈服后的βnwp,n均无明显变化。同时求得了外推的零韧带断裂位移e0,b和最大载荷P0,y,随厚度增大,前者具有一定的下降趋势,后者则显示出较大的增长趋势。This paper studied the influence of compressed specimen thickness to fracture parameters of a co-polypropylene. The fracture behavior of the deeply double edge notched tension specimens were studied by the essential work of fracture method. The results show that while thickness increases in the range from 0.6 mm to 1.1 mm, the fracture toughness ωe of copolypropylene reduces by over 30%. The main reason is that as thickness increases the specific essential work of fracture for yielding ωe,y doesn＇t seem to vary while that for necking and subsequent fracture we,a decreases. Results also show that as thickness increases, the specific plastic work item βωp doesn＇t vary much, since neither the specific plastic work for yielding βyωp,y nor that for necking and subsequent fracture βnωp,n varies. Another two parameters as ligament length extrapolates toward zero, fracture displacement e0,b and max load P0,y, are also studied. When thickness increases, the former tends to fall slightly while the latter rises obviously.

关 键 词：共聚聚丙烯 断裂行为 基本断裂功 塑性功 

分 类 号：O631.21[理学—高分子化学]