Qin Guoshuai, Lu Chunsheng, Zhang Xin, Zhao Minghao
School of Mechanics and Engineering Science, Zhengzhou University, Zhengzhou 450001, Henan, China.
School of Civil and Mechanical Engineering, Curtin University, Perth, WA 6845, Australia.
Materials (Basel). 2018 Oct 16;11(10):2000. doi: 10.3390/ma11102000.
In this paper, the fracture behavior of GaN piezoelectric semiconductor ceramics was investigated under combined mechanical and electric loading by using three-point bending tests and numerical analysis. The experimental results demonstrate that, in contrast to traditional insulating piezoelectric ceramics, electric current is a key factor in affecting the fracture characteristics of GaN ceramics. The stress, electric displacement, and electric current intensity factors were numerically calculated and then a set of empirical formulae was obtained. By fitting the experimental data, a fracture criterion under combined mechanical and electrical loading was obtained in the form of an ellipsoid function of intensity factors. Such a fracture criterion can be extended to predict the failure behavior of other piezoelectric semiconductors or devices with a crack, which are useful in their reliability design and applications.
本文通过三点弯曲试验和数值分析，研究了GaN压电半导体陶瓷在机械和电联合加载下的断裂行为。实验结果表明，与传统绝缘压电陶瓷不同，电流是影响GaN陶瓷断裂特性的关键因素。通过数值计算得到了应力、电位移和电流强度因子，进而得到了一组经验公式。通过拟合实验数据，得到了以强度因子的椭球函数形式表示的机械和电联合加载下的断裂准则。这种断裂准则可扩展用于预测其他含裂纹的压电半导体或器件的失效行为，对其可靠性设计和应用具有重要意义。
