摘要
根据聚甲基丙烯酸甲脂圆棒试样切口根部及裂尖钝化的应力应变特性 ,推导了聚甲基丙烯酸甲脂断裂韧性与临界切口半径 ρc的关系式。ρc 是材料常数 ,且当切口半径 ρ<ρc 时 ,尖切口问题转化为钝化的裂纹问题 ,此时应按断裂力学方法处理相关问题。实验结果表明 ,所测两种典型聚甲基丙烯酸甲脂的ρc>0 .2 5mm,因而 ,圆棒尖切口试样用于断裂韧性的估算具有现实的可行性。提出了一种简便的通过尖切口拉伸试验估算聚甲基丙烯酸甲脂断裂韧性的方法。
The formula on the relationship between the fracture toughness ( K IC ) of PMMA and the critical radius ( ρ c) of notch root has been deduced by analyzing the characteristics of stress and strain at notch and crack tip. It is shown that the value of ρ c is a material constant and when the notch root radius ρ<ρ c, the problems of sharp notch are changed into the issues of blunt crack. Thus, the theory of fracture mechanics has been introduced to solve these problems. The test results showed that the PMMA critical radius ρ c>0.25mm, and there is the practical feasibility in measurement of the fracture toughness of PMMA by circumferentially notched round bar specimens and the technique of measurement is presented in this paper.
出处
《理化检验（物理分册）》
CAS
2000年第10期435-437,共3页
Physical Testing and Chemical Analysis(Part A:Physical Testing)
