基于微型镓基共晶固定点的温度传感器在轨校准方法研究

介绍了微型镓基共晶固定点的灌注工艺和准绝热相变特性测量系统;结合空腔黑体和非近位安装的温度传感器,研究了Ga-Sn和Ga-Zn共晶固定点的相变温坪重复性和Ga固定点的相变温坪长期稳定性;通过特定的热环境下镓及2个镓基共晶固定点三者熔化过程中温度传感器测量到的相变温坪值,对嵌入空腔黑体底部的温度传感器进行校准,其校准结果与实验室常规校准方法得到的结果差异均小于2mK。实验结果表明:在热环境保持不变的条件下,随着相变时间的增加,相变温坪值就越靠近理论上相变物质的熔化温度,即固定点与温度传感器测孔之间的异位温差越小;对于Ga-Sn和Ga-Zn共晶固定点,温度传感器测量到的相变温坪值与加热功率呈线性关系,零功率下的单点校准温度分别为20.352℃和25.187℃。

On - Orbit Calibration of Temperature Sensor based on Miniature Gallium - based alloy Fixed point

A calibration method of the on-orbit temperature sensor based on the gallium - based alloy miniature fixed point is proposed. The developed process of the Gallium - based alloy miniature fixed points for on-orbit calibration and the quasi-adiabatic vacuum measurement system are introduced. Combined with cavity blackbody and non-proximal mounted temperature sensor, the repeatability of Ga-Sn and Ga-Zn alloy fixed points is measured,which was better than 2mK during melting process. For Ga, the long-term stability is 2.1mK. The temperature sensor at the bottom of cavity blackbody was indexed by the continuous melting plateau value measured by temperature sensor during gallium and two gallium-based alloy fixed points melting process in a specific thermal environment. The difference between the calibration result and the routine calibration method in the laboratory is less than 2mK. The results are also shown as the phase transformation time increases, the phase transition temperature is closer to the melting temperature of the phase change material, ie, the smaller the temperature difference between the fixed point and the temperature sensor hole, in the thermal environment conditions remaining unchanged. Meanwhile, for Ga-Sn and Ga-Zn, there is a linear relationship between the phase transition melting temperature and the single-point calibration temperature at zero power is 20.352°C and 25.187°C.