Determination of acoustic wave velocities and elastic properties for diamond and other hard materials
Determination of acoustic wave velocities and elastic properties for diamond and other hard materials
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DOI：
10.1016/j.matchemphys.2004.02.003
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发表时间：
2004-06
影响因子：
4.6
通讯作者：
Sea-Fue Wang;Y. Hsu;Jui-Chen Pu;J. Sung;L. Hwa
中科院分区：
文献类型：
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作者：
Sea-Fue Wang;Y. Hsu;Jui-Chen Pu;J. Sung;L. Hwa
单晶金刚石，铌酸锂，钽酸锂，硅，和各种多晶硬质材料被用来测量室温超声速度利用脉冲回波法。然后根据波速计算弹性常数。结果表明，金刚石[111]方向具有最快的纵波速度（19039 ms-1）和最大的杨氏模量（1223 GPa）。多晶CVD金刚石的声波速度和杨氏模量与单晶金刚石相似，但远大于Co或SiC结合的多晶金刚石。多晶CVD金刚石中晶界的存在对声波的传播没有明显的影响。立方氮化硼（cBN）、硅和金刚石都具有立方结构，但由于键性质和键长的不同，它们的波速和弹性常数都不如金刚石。讨论了声波速度和弹性常数与晶体结构和比重的关系。
Single crystal of diamond, LiNbO3, LiTaO3, silicon, and various polycrystalline hard materials were used to measure the room temperature ultrasonic velocity utilizing a pulse-echo method. The elastic constants were then calculated from the wave velocities. The results indicate that [111] direction of diamond possesses the fastest longitudinal wave velocity (19039ms−1) and the largest Young’s modulus (1223GPa). Acoustic wave velocity and Young’s modulus of polycrystalline CVD diamond are similar to those of single crystal diamond, but much larger than Co or SiC bonded polycrystalline diamonds. The existence of grain boundary at the polycrystalline CVD diamond does not significantly affect the propagation of the acoustic wave. Cubic boron nitride (cBN), silicon and diamond possess cubic structure, however, the wave velocity and elastic constant of cBN and Si are inferior to diamond, due to the differences in the bond nature and bond length. The dependents of acoustic wave velocity and elastic constant on the crystal structure as well as specific gravity are discussed.