超大面阵红外探测器冷平台支撑结构研究

为满足拼接式超大面阵型红外探测器的空间应用需求，超大规模冷平台组件需要在低温下工作，冷平台支撑结构需要较高的刚度以满足组件的抗振动性能，又需要较高的结构热阻以降低其传导漏热。提出了对称式八杆结构作为冷平台支撑，该支撑结构采用新型的高强度、低热导率的氧化锆陶瓷材料。基于有限元软件分析了支撑结构的高度、安装倾斜角度、宽厚比和材料对于组件的模态基频、支撑结构热阻以及组件在30 g静力学载荷下的最大应力的影响，通过对比选取了其中一组参数设计了实际的测试组件，支撑的结构热阻达到了220 K/W，对组件进行了5～2 000 Hz的正弦扫频试验、总均方根为9 g RMS的XYZ三个方向的随机振动等力学环境试验，最终组件通过了空间环境适应性试验验证，组件的基频达到了560 Hz，并且测试结果与仿真结果趋势符合较好。结果表明：对称式八杆氧化锆支撑结构解决了超大面阵型红外探测器冷平台组件既需要高力学性能又需要低漏热的难题，满足工程化应用需求。

Research on the supporting structure of the cold platform of the large format infrared detector

In order to meet the space application requirements of the large format Mosaic infrared detector, ultra-scale cold platform need to work at low temperatures, and the cold platform support structure requires high rigidity to meet the components' anti-vibration performance, and a high structure thermal resistance to reduce its conduction heat leakage. A symmetrical eight-bar structure is proposed as the cold platform support, which adopts a new type of zirconia ceramic material with high strength and low thermal conductivity. Based on the finite element software, the influence of the height of the support structure, the installation inclination angle, the aspect ratio and the material on the modal fundamental frequency of the module, the thermal resistance of the support structure and the maximum stress of the module under 30 g static load are analyzed. A set of parameters is used to design the actual test component, the thermal resistance of the support structure reaches 220 K/W, and the components are subjected to a 5-2 000 Hz sine frequency sweep test, a total root mean square of 9 g RMS, and random vibration in the three directions of XYZ and other mechanics. In the environmental test, the final component passes the experimental verification of space environment adaptability. The fundamental frequency of the component reaches 560 Hz, and the test results are in good agreement with the simulation results. The results show that the symmetrical eight-rod zirconia support structure solves the problem that the cold platform of the large format infrared detector requires both high mechanical properties and low heat leakage, and meets the needs of engineering applications.