Durability of Adhesive Bonds: Accelerated Testing by Ultrasonic Loading and Mechanistic Modeling

该项目解决了粘合剂在超过1000万次循环的超长寿命区域内防止疲劳失效的耐久性问题。一种基于压电陶瓷致动器的加速测试方法将被使用，该致动器可以提供高达50,000 Hz的大应变/应力致动。由于快速循环和频率相关的失效行为引起的热产生等并发症将在实验和理论上进行研究。系统研究了不同力学载荷和环境条件下粘接接头的疲劳损伤机理和损伤演化过程。将发展损伤机制的微观力学模型，并将其与连续介质力学计算相结合，以预测粘接节点在循环荷载下的结构耐久性。

This project addresses the durability of adhesive bonds against failure due to fatigue in the ultra-long life region of over 10 million cycles. An accelerated testing method will be used based on piezoelectric ceramic actuators which can supply large strain/stress actuation at frequencies up to 50,000 Hz. Complications such as heat generation due to the rapid cycling and frequency dependent failure behavior will be examined experimentally and theoretically. Fatigue damage mechanisms and damage evolution processes in the adhesive joints under different mechanical loading and environmental conditions will be systematically investigated. Micro-mechanial models of damage mechanisms will be developed and integrated with continuum mechanics calculations to predict the structural durability of adhesive joints under cyclic loading.