Damage depth is an important dynamic parameter for describing the degree of material damage and is also a key fundamental issue in the field of impact compression technology.The present work is dedicated to the damage...Damage depth is an important dynamic parameter for describing the degree of material damage and is also a key fundamental issue in the field of impact compression technology.The present work is dedicated to the damage depth of shock-melted metal in microspall under triangular wave loading,and an improved model of damage depth considering the material's compressibility and relative movement is proposed.The damage depth obtained from the proposed model is in good agreement with the laser-driven shock loading experiment.Compared with the previous model,the proposed model can predict the damage depth of shock-melted metal in microspall more accurately.Furthermore,two-groups of the smoothed particle hydrodynamics(SPH)simulations are carried out to investigate the effects of peak stress and decay length of the incident triangular wave on the damage depth,respectively.As the decay length increases,the damage depth increases linearly.As the peak stress increases,the damage depth increases nonlinearly,and the increase in damage depth gradually slows down.The results of the SPH simulations adequately reproduce the results of the proposed model in terms of the damage depth.Finally,it is found that the threshold stress criterion can reflect the macroscopic characteristics of microspall of melted metal.展开更多
以中国科学院武汉岩土力学研究所研制的RMT-150C岩石力学试验系统为主要试验平台,以宜昌砂岩为研究对象,对砂岩在96 k N峰值、不同频率、不同波形加载下的垂向力变化速率、垂向变形速率、表观弹性模量、横向变形速率、瞬时泊松比与时间...以中国科学院武汉岩土力学研究所研制的RMT-150C岩石力学试验系统为主要试验平台,以宜昌砂岩为研究对象,对砂岩在96 k N峰值、不同频率、不同波形加载下的垂向力变化速率、垂向变形速率、表观弹性模量、横向变形速率、瞬时泊松比与时间的关系等5方面内容进行分析得出不同频率、不同波形对上述关系的影响规律。在提出非滞后时间段内表观弹性模量与垂直力线性关系的基础上,给出不同频率下三角波和正弦波的计算公式及参数,计算和实测对比证明,其计算公式可以很好地拟合不同波形、不同频率下的变形速率随时间的毫秒级变化规律。在此基础上,给出了三角波和正弦波的能量计算方法,对比分析显示,计算公式和方法可以很好地对三角波和正弦波在不同频率和不同加载速度下的能量值作出毫秒级的精确预测。展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.U1530261 and 11572054)the Science Challenge Project,China(Grant No.TZ2016001).
文摘Damage depth is an important dynamic parameter for describing the degree of material damage and is also a key fundamental issue in the field of impact compression technology.The present work is dedicated to the damage depth of shock-melted metal in microspall under triangular wave loading,and an improved model of damage depth considering the material's compressibility and relative movement is proposed.The damage depth obtained from the proposed model is in good agreement with the laser-driven shock loading experiment.Compared with the previous model,the proposed model can predict the damage depth of shock-melted metal in microspall more accurately.Furthermore,two-groups of the smoothed particle hydrodynamics(SPH)simulations are carried out to investigate the effects of peak stress and decay length of the incident triangular wave on the damage depth,respectively.As the decay length increases,the damage depth increases linearly.As the peak stress increases,the damage depth increases nonlinearly,and the increase in damage depth gradually slows down.The results of the SPH simulations adequately reproduce the results of the proposed model in terms of the damage depth.Finally,it is found that the threshold stress criterion can reflect the macroscopic characteristics of microspall of melted metal.
文摘以中国科学院武汉岩土力学研究所研制的RMT-150C岩石力学试验系统为主要试验平台,以宜昌砂岩为研究对象,对砂岩在96 k N峰值、不同频率、不同波形加载下的垂向力变化速率、垂向变形速率、表观弹性模量、横向变形速率、瞬时泊松比与时间的关系等5方面内容进行分析得出不同频率、不同波形对上述关系的影响规律。在提出非滞后时间段内表观弹性模量与垂直力线性关系的基础上,给出不同频率下三角波和正弦波的计算公式及参数,计算和实测对比证明,其计算公式可以很好地拟合不同波形、不同频率下的变形速率随时间的毫秒级变化规律。在此基础上,给出了三角波和正弦波的能量计算方法,对比分析显示,计算公式和方法可以很好地对三角波和正弦波在不同频率和不同加载速度下的能量值作出毫秒级的精确预测。
