【摘要】 采用直槽式和尖槽式中心切口圆盘试件,对有机玻璃在纯Ⅰ型准静态加载条件下的断裂行为进行了实验研究。结果表明,中心切口圆盘试件的切口形状对断裂行为和断裂韧度的测试结果有显著的影响。直槽切口偏离理想裂纹,裂纹起裂始于切口端部的角点,实测的断裂韧度值偏高且具有尺寸相关性;尖槽切口接近理想裂纹,裂纹起裂始于尖角的顶点,实测的断裂韧度不存在尺寸相关性,即是材料常数。更多还原

【Abstract】 For polymethyl methacrylate(PMMA),pure mode I fracture tests were performed under quasi-static loading by using central notched circular disk specimen.The experimental results show that the notch shape has a great effect on the fracture behavior and fracture toughness measurement of brittle materials.For straight notch specimen,the crack propagation begins at the corner of the notch and the measured fracture toughness is dependent on the specimen geometry.However,for the specimen that has a sharp notch close to an ideal crack,the measured fracture toughness is not sensitive to the specimen geometry.更多还原