金瓷双材料力学行为的现代光力学实验研究

Experimental Study of Mechanics Behaviors of Metal-porcelain Bi-material by Modern Photo-mechanics Methods

金瓷修复体兼具金属强度及陶瓷美观的优点,在口腔医学上得到了广泛应用,但临床上时有发生脱瓷并且又多发生在界面处,针对这种情况,通过研究不同层厚比的金瓷修复体试件梁的界面力学行为,以分析其破坏机理。采用云纹干涉法和电子散斑法对界面具有缺陷形式的试件进行了实验研究。得到裂纹尖端及界面处的位移场,计算了界面断裂强度等参量,并给出了试件制备、实验方法。实验结果表明不同层厚比的试件以及不同界面缺陷形式的试件对抵抗破坏能力均有不同影响;现代光力学实验方法对研究具有小变形的双材料结构力学行为可行、有效。

Porcelain-fused-to-metal （PFM） is widely used in dental clinic because of its intensity of metal and finery of porcelain. However porcelain often flakes off in the interface of metal and porcelain. To this problem, the interracial mechanical behaviors of different thickness ratios of PFM are studied for analyzing failure mechanism. Results will be as reference for technique in clinic. Moiré interferometry and electronic speckle pattern interferometry are applied in the experiment study for the specimens with interracial crack, no interracial crack and vertical interface crack. Displacement fields of crack tip and near interface are obtained, stress intensity factor （SIF） also is calculated. In addition, the preparation process of specimen and experimental methods are also introduced. The results of experiments indicate that specimens with different thickness ratios and different interface deficiencies are different in the ability of resisting destruction. In addition, it shows that methods of modern photo-mechanics are feasible and effective in studying mechanics behaviors of bi-material structure with little displacement.