Development of thermal fatigue sensor for electrical and electronic equipment

In this paper, authors proposed an original sensor which can measure thermal fatigue life of electronic equipment. The measurement principle of the sensor is that the joint was damaged by the stress due to a mismatch of thermal expansion between two materials. Finally, the joint was ruptured by the repeated stress. The priority subject was the feasibility of measurement accuracy of the sensor. Generally, a high level control of failure in joint is very difficult. To solve this problem, authors conceived the original design of the sensor. Then, the availability study of the original sensor for fracture control in joint was carried out using the crack propagation analysis. In the result, a high level control method for failure in joint of the sensor was achieved.