氧化铝陶瓷SHPB加载下的数值模拟研究

利用微裂纹扩展区模型,在JH-2本构模型中增加了类似于TCK本构模型的拉伸损伤因子,编制了材料本构模型子程序,并将其嵌入到LS-DYNA970有限元软件中,对SHPB实验进行了数值模拟。结果表明,Weibull参数k对陶瓷试样的拉伸损伤有较大的影响,当Weibull参数k值小于1×1020时,试样破坏是压缩破坏;当Weibull参数k超过1×1028时,试样破坏是拉伸损伤破坏。当载荷超过陶瓷压缩强度时,含初始裂纹氧化铝陶瓷的破坏形式是拉伸损伤和压缩破坏共同作用的结果;当载荷小于陶瓷压缩强度时,JC陶瓷破坏是拉伸损伤作用的结果。

Simulation Study of Alumina Ceramics under SHPB Loading

Based on the model of the domain ofmicrocrack growth（DMG）, the tensile damage factor similar to TCK model is added to the modified JH-2 model. The material constitutive subroutine is programmed, and is embedded into LS-DYNA970 by the interface files. The crack growth modes of tensile loading and compressive loading are simulated with the new appended constitutive model of LS-DYNA970. The calculation results indicate that Weibull parameter k affects the tensile damage. The failure of ceramic specimens is tensile damage if Weibull parameter k is greater than 1×10^28, and the failure of ceramic specimens is compressive damage if Weibull parameter k is less than 1×10^20. The ceramic failure under one dimension stress loading is activated by tensile damage and compressive damage together when the dynamic load is greater than the quasi-static compressive strength, and the cause of failure is the tensile damage when the dynamic load is less than that.