Split Hopkinson pressure bar(SHPB) apparatus, usually used for testing behavior of material in median and high strain-rate, is now widely used in the study of rock dynamic constitutive relation, damage evolvement mech...Split Hopkinson pressure bar(SHPB) apparatus, usually used for testing behavior of material in median and high strain-rate, is now widely used in the study of rock dynamic constitutive relation, damage evolvement mechanism and energy consumption. However, the possible reasons of sampling disturbance, machining error and so on often lead to the scattering of test results, and bring ultimate difficulty for forming general test conclusion. Based on the stochastic finite element method, the uncertain parameters of specimen density ρs, specimen radius Rs, specimen elastic modulus Es and specimen length Ls in the data processing of SHPB test were considered, and the correlation between the parameters and the test results was analyzed. The results show that the specimen radius Rs has direct correlation with the test result, improving the accuracy in preparing and measuring of specimen is an effective way to improve the accuracy of test and minish the scattering of results for SHPB test.展开更多
棒材是国内产量占比较大的钢材品种,为了保证棒材质量,需对其实施无损检测。相控阵超声换能器基于惠更斯原理设计,通过电子激发控制实现超声声束的聚焦和偏转。水浸相控阵超声设备扫查效率快、灵敏度高,能够实现棒材全截面扫查,适用于...棒材是国内产量占比较大的钢材品种,为了保证棒材质量,需对其实施无损检测。相控阵超声换能器基于惠更斯原理设计,通过电子激发控制实现超声声束的聚焦和偏转。水浸相控阵超声设备扫查效率快、灵敏度高,能够实现棒材全截面扫查,适用于棒材产品的无损检测。使用相控阵超声设备前要对所有聚焦法则进行均一性校准,保证各聚焦法则的检测灵敏度差异在既定范围内。通过棒材检测实践,验证了水浸相控阵超声设备能够在500 mm/s进给速度下检测出棒材中大于0.7 mm FBH当量的夹杂物。展开更多
基金Projects(50490274, 50534030) supported by the National Natural Science Foundation of ChinaProject supported by the Natural Science Foundatin of Hunan Province, China
文摘Split Hopkinson pressure bar(SHPB) apparatus, usually used for testing behavior of material in median and high strain-rate, is now widely used in the study of rock dynamic constitutive relation, damage evolvement mechanism and energy consumption. However, the possible reasons of sampling disturbance, machining error and so on often lead to the scattering of test results, and bring ultimate difficulty for forming general test conclusion. Based on the stochastic finite element method, the uncertain parameters of specimen density ρs, specimen radius Rs, specimen elastic modulus Es and specimen length Ls in the data processing of SHPB test were considered, and the correlation between the parameters and the test results was analyzed. The results show that the specimen radius Rs has direct correlation with the test result, improving the accuracy in preparing and measuring of specimen is an effective way to improve the accuracy of test and minish the scattering of results for SHPB test.
文摘棒材是国内产量占比较大的钢材品种,为了保证棒材质量,需对其实施无损检测。相控阵超声换能器基于惠更斯原理设计,通过电子激发控制实现超声声束的聚焦和偏转。水浸相控阵超声设备扫查效率快、灵敏度高,能够实现棒材全截面扫查,适用于棒材产品的无损检测。使用相控阵超声设备前要对所有聚焦法则进行均一性校准,保证各聚焦法则的检测灵敏度差异在既定范围内。通过棒材检测实践,验证了水浸相控阵超声设备能够在500 mm/s进给速度下检测出棒材中大于0.7 mm FBH当量的夹杂物。