宽量程真空传感器可靠性强化试验及故障分析

面向宽量程真空传感器研发阶段的可靠性优化,设计低温步进、高温步进、快速温变、振动步进和综合环境5项可靠性强化试验,并搭建真空对比测试系统。在经历每项可靠性强化试验后,对比试验获得被测传感器和标准传感器测试不同真空度的示值。真空测试和可靠性分析结果表明,被测传感器的全温区温度可靠性较好,但振动步进试验使1只传感器发生故障,电离灯丝断裂、引线针与陶瓷基座间的钎焊裂纹、可伐环与陶瓷基座间的钎焊孔洞是被测传感器试验和使用故障的主要原因。从优化管芯结构设计、自动化灯丝焊接工艺、优化钎焊工艺等方面提出传感器可靠性优化建议。此外,虽然被测传感器相对标准传感器的测量误差较大,但被测传感器之间的输出一致性较好,可从后端补偿上提高传感器测量精度。

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.