惯性器件加速贮存环境性能变化规律及失效机理

目的研究惯性器件的加速贮存环境性能退化规律,分析失效薄弱环节及其失效机理。方法开展惯性器件的加速贮存试验,进行惯性器件的零偏、标度因数的检测,用扫描电子显微镜、红外显微仪、气-质联用仪等分析仪器,监测微观组织、结构损伤情况。针对石英挠性加速度计在加速贮存试验过程中的变化行为,分析温度环境因素对其损伤的微观作用机制,解释宏观性能退化内在原因。结果惯导系统中,石英挠性加速度计在加速贮存试验4个周期后,其零偏超出阈值范围。结论惯导系统中的薄弱环节为石英挠性加速度计的粘结剂。在加速贮存试验过程中,粘结剂中的增塑剂邻苯二甲酸二异辛酯(DEHP)发生分解生成挥发物,环氧树脂胶618的双酚A也少量挥发。当石英挠性加速度计从高温冷却至室温,检测宏观性能时,两种挥发物沿摆片移动至摆片底部,与力矩器镜面形成粘连,使摆片无法进行有效的工作(摆动)。

Performance Change Law and Failure Mechanism of Inertial Devices in Accelerated Storage Environment

Objective To research the accelerated storage performance degradation rules and analyze the weakness and the failure mechanisms of inertia device. Methods Accelerated storage test of inertial devices was developed; the zero offset of quartz flexible accelerometer was tested; and the microstructure and structural damage were detected by electron microscopy, infrared microscopy and gas chromatography-mass spectrometry. In allusion to changes of quartz flexible accelerometer in the accelerated storage test, the microcosmic mechanism of environmental factors such as temperature was analyzed; and the internal cause of the degradation of macro properties was explained. Results In the inertial navigation system, the zero bias of the quartz flexible accelerometer exceeded the threshold value after 4 cycles of high temperature test. Conclusion The weakness of the inertial navigation system is the binder in the quartz flexible accelerometer. During the high temperature test, the plasticizer of di (2-ethylhexyl) phthalate (DEHP) is decomposed to volatile matter, and the biphenyl A of epoxy resin is also volatilized. When the accelerometer is cooled from high temperature to room temperature, the two kinds of volatiles are moved to the bottom of the pendulum according to the pendulum, and the surface of the torque sensor is adhered. As a result, the pendulum cannot work effectively.