Reliability Enhancement Test and Fault Analysis of Wide-Range Vacuum Sensor

Five reliability enhancement tests are designed for developing the wide-range vacuum sensor,including low temperature stepping,high temperature stepping,rapid temperature change,vibration stepping and comprehensive test,and a vacuum comparison test system is built. After each reliability enhancement test,the indication values of different vacuum tested by the tested sensor and the standard sensor were obtained. The results of the vacuum test and reliability analysis show that the temperature reliability of the tested sensors is good,but one sensor failed in the vibration stepping test. The main causes of sensor failure in test and use are the fracture of ionization filament,the brazing crack between the lead pin and ceramic base,and the brazing hole between Kovar ring and ceramic base,etc. Some optimization suggestions are put forward from the aspects of optimizing the structure design of the tube core,automatic filament welding process and optimizing brazing process,etc. In addition,the relative error of the tested sensors is larger,but the output consistency between the tested sensors is better,so the measurement accuracy of the tested sensor can be improved from the back-end compensation.