摘要
获得PVC材料的J-R阻力曲线以及断裂韧度J_(IC)的难点在于裂纹扩展量Δa的测量,传统染色处理以及三维测量等方法过程复杂且测试成本高。由于塑料的易切割性,可以简化Δa的测量过程。因此,基于多试样法,提出根据规范的测点要求对加载后的试件沿着裂纹纵向切割成若干片、再通过工业电子显微镜测量每个切割片上的裂纹长度,从而获得Δa的二维测量方法。通过GB 21143—2014和ASTM D6068-10两个标准,应用该方法均能获得相对一致的J-R阻力曲线和J_(IC)值,测试结果有效且准确。其中根据GB 21143—2014获得PVC的J_(IC)值为8.03 kJ/m^(2),J-R阻力曲线拟合方程的系数为9.93,指数为0.15;根据ASTM D6068-10获得PVC的J_(IC)为8.31 kJ/m^(2),J-R阻力曲线拟合方程的系数为12.7,指数为0.3;表明ASTM D6068-10获得PVC的断裂韧度J_(IC)值和拟合方程的系数、指数均大于GB 21143—2014。由于PVC材料与金属材料性能的差异,得出ASTM D6068-10更适用于测试PVC材料的J-R阻力曲线和J_(IC)值的结论。该方法将传统的裂纹染色处理和三维测量等复杂操作简化为切片和二维测量,简化测量过程,降低了测量成本,可普及应用于塑料断裂韧性的测量。
The difficulty of obtaining J-R resistance curve and fracture toughness J_(IC)of PVC materials lies in the measurement of crack growth amountΔa.Traditional dyeing treatment and 3D measurement methods make the testing process complicated and expensive.Due to the easy cutting of plastics,the measurement process ofΔa can be simplified.Based on the multi-sample method,a 2D measurement method was proposed to measureΔa.The method is to cut the loaded specimen into several pieces longitudinally along the crack according to the requirement of the standard measurement point,and then measure the crack length on each cut piece through the industrial electron microscope to obtainΔa.Using this method,relatively consistent J-R resistance curves and J_(IC)values can be obtained through both GB 21143—2014 and ASTM D6068-10 standards,and the test results are valid and accurate.According to GB 21143—2014,the obtained J_(IC)value of PVC is 8.03 kJ/m^(2),the coefficient of J-R resistance curve fitting equation is 9.93,and the index is 0.15.According to ASTM D6068-10,the obtained J_(IC)value of PVC is 8.31 kJ/m^(2),the coefficient of J-R resistance curve fitting equation is 12.7,and the index is 0.3.The results show that the fracture toughness J_(IC)value and the coefficient,exponent of the fitting equation obtained by ASTM D6068-10 are all higher than that obtained by GB 21143—2014.Due to the difference in performance between PVC and metal materials,ASTM D6068-10 standard is more suitable for testing the J-R resistance curve and J_(IC)value of PVC materials.The method simplifies the complex operations such as traditional crack dyeing treatment and 3D measurement to cutting slices and 2D measurement,simplifies the measurement process,reduces the measurement cost,and can be widely applied in the measurement of fracture toughness of plastic materials.
作者
黄建伟
唐鹏飞
潘栋
石拓
莫淑蓓
李颢旭
HUANG Jianwei;TANG Pengfei;PAN Dong;SHI Tuo;MO Shubei;LI Haoxu(Guangxi Communications Design Group Co.,Ltd.,Nanning 530029,China;School of Civil Engineering and Architecture,Guangxi University,Nanning 530004,China;Guangxi Traffic Engineering Testing Co.,Ltd.,Nanning 530004,China;Guangxi Road Construction Engineering Group Co.,Ltd.,Nanning 530021,China;Guangxi Technological College of Machinery and Electricity,Nanning 530007,China)
出处
《压力容器》
北大核心
2024年第7期25-31,共7页
Pressure Vessel Technology
基金
交通运输行业重点科技项目(2022-ZD7-127)
中国博士后科学基金面上项目“地区专项支持计划”(2023MD744182)。
