(1. 北京空间飞行器总体设计部，北京 100094；
2. 中南大学粉末冶金国家重点实验室，长沙 410083)
摘 要: 压电纤维复合物因具有较大的驱动应变和良好的柔韧性而成为智能材料领域的研究热点之一。采用有限元法分析各结构参数对压电纤维复合物驱动应变性能的影响规律。结果表明：电场在交叉指形电极边缘发生聚集，且在此区域的电场强度约为均匀部分电场强度的4倍，因此，应用过程中压电纤维极易在电极边缘部分因应力集中而产生裂纹，从而降低复合物的驱动性能；指间距越大，复合物的驱动应变量及电场分布越接近于理想情况；采用高体积分数的压电陶瓷纤维、电极与纤维之间较小的聚合物层厚度均有利于提高智能压电纤维复合物的驱动应变性能；方形压电纤维复合物较圆形压电纤维复合物的驱动应变性能至少可提高60%。
关键字: 压电纤维复合物；有限元法；压电陶瓷纤维；应变性能
（1. Beijing Spacecraft System Engineering, Beijing 100094, China;
2. State Key laboratory of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:The piezoelectric fiber composites become one research focus of smart materials due to the larger strain and better stiffness than those of other piezoelectric composite. The influence of structural parameters on actuation strain property of piezoelectric composites was studied by the finite element analysis. The modeling results show that the high electric field near the electrode edge is four times larger than that in the middle of the fiber where the electric field is uniform. So in this area, the piezoelectric fiber easily cracks due to the stress concentration, which leads to the failure of composite. The electric field and the strain are close to the ideal actuator with the increase of the electrode separation. The performance of composite increases by using higher volume of the piezoelectric fiber and smaller thickness of polymer between the fiber and electrode. Compared with the circular fiber composites, the strain property of the square fiber composite is improved at least 60%.
Key words: piezoelectric fiber composites; finite element method; piezoelectric ceramic fiber; strain property
