几种生物陶瓷材料的裂纹扩展特性

采用破坏力学中的双扭矩实验法，研究了玻璃陶瓷、云母陶瓷、氧化铝陶瓷、氧化锆陶瓷材料分别在大气、水环境中的静负荷和循环负荷下的裂纹扩展特征，阐明了水环境和循环负荷对材料裂纹扩展特性（KI－V特征）的影响。所研究的材料在水环境下的裂纹扩展速度均加快，但玻璃陶瓷和氧化锆陶瓷材料更为明显。在静负荷下这几种材料的裂纹扩展阻力由小到大的次序为：玻璃陶瓷（N－0），玻璃陶瓷（N－11），云母陶瓷，氧化锆陶瓷和氧化铝陶瓷，对于氧化铝和氧化锆陶瓷材料在循环负荷下的裂纹扩展速度均明显加快。

BEHAVIOR OF CRACK PROPAGATION IN SOME BIO-CERAMICS

Most of bio-ceramics are oxide ceramics, and they undergo fatigue by stress corrosion cracking. In this paper, the effects of water environment and cyclic loading on the KI-V characteristics were studied by the crack growth tests using double torsion (DT) method under static and cyclic loading in both environments of air and water for the bio-ceramics of glass ceramics, mica glass ceramics, alumina and zirconia. The increase in the crack velocity of all materials in water environment is observed, but the degree is more remarkable for glass ceramics and zirconia. The order of the crack propagation resistance under static loading is shown hereunder: Neoceram N-0 < Neoceram N-11 < Mica Glass < Zirconia < Alumina. The increase in the crack velocity under the condition of cyclic loading is clearly observed in alumina and zirconia.