Shock Compression Behaviors and the Correlation with Microstructures of Ceramic Materials

陶瓷材料硬而脆，具有很大的晶体各向异性。陶瓷的屈服和非冲击压缩相变强烈地依赖于它们的特性。本研究通过冲击波测量和高质量试件的恢复实验，研究了各种陶瓷材料的冲击屈服特性、高压相变、状态方程等与材料特性的关系。利用熊本大学的火药枪、东北大学的二级轻气炮和高速镜面旋转式扫描相机进行了冲击压缩实验，研究了立方和四方氧化锆高压相的弹塑性相变、相变和状态方程，阐明了晶体结构和晶态的影响。在四方氧化锆上发现了异常的Hugoniot和大层裂性质，并与ph…相关对更多的ASE过渡进行了讨论。研究了Si3N4块体陶瓷和碳化硅晶须掺杂陶瓷的显微结构对强度的影响。测定了AIN的Hugoniot压缩曲线，研究了AIN的弹塑性相变和相变、状态方程以及晶粒度的影响。在B_4C多晶和Al_2O_3单晶上观察到弹性区和塑性区自由表面的锯齿状轮廓，表明裂纹在弹塑性转变中起重要作用。测量了LiF单晶的各向异性HEL值，测量了ZS和ZUSE的Hugoniot压缩曲线，确认了ZUS和ZSe的相变，发现了一种新的相变。自行研制的激光速度干涉仪(VISAR)成功地测量了钢的质点速度历史。此外，还制作了用于光学测量的长脉冲激光倍频激光器。较少

Ceramic materials are hard but brittle, and have large crystal anisotropy. The yielding and phase transition unser shock compression of ceramics strongly depend on their characterizations. In this study, the shock yielding property, high-pressure phase transition, equation of state, etc.of various kinds of ceramic materials ant the correlation with material characterizations were investigated by the shock-wave measurements and recovery experiments using high-quality specimens. The shock compression experiments were performed by using a powder gun of Kumamoto University, a two-stage light gas gun of Tohoku University and the high-velocity mirror-rotating type streak cameras.The elastoplastic transition, phase transition and EOS of the high-pressure phase of the cubic and tetragonal zirconia were studied, and the effects of crystal structure and crystal state were clarify. The anomalous Hugoniots and large spall property were found on the tetragonal zirconia, and the correlations with ph … More ase transition were discussed. The effects of microstructure on the strength were investigated on monolithic Si_3N_4 ceramics and the SiC whisker-doped ceramics. The Hugoniot compression curve of AIN was measured, and the elastoplastic transition and phase transition, equation of state and also the effect of crystal grain were studied. The jagged profiles of free-surface in elastic and plastic region were observed on B_4Cpolycrystal and Al_2O_3 single crystal, which indicated that cracks playd an important role in the elstoplastic transition. The anisotropic HEL of LiF single crystal was measured.The Hugoniot compression curves of ZnS and ZuSe were measured, and the phase transitions were confirmed on ZuS and ZnSe and a new phase transition was found on ZnS.The VISAR system (Laser-Velocity Interferometer) was produced ourselves, and the particle-velocity history of a steel was succeeded in measurement. In addition, a long pulsed YAG double frequency lase was also produced for the optical measurements. Less