高温超导直接冷却的氮化铝与无氧铜接触界面热阻的实验研究

氮化铝(AlN)具有高热导性、高电绝缘性,是超导二元电流引线热截流结构中常用的材料之一。根据稳态导热法建立低温真空实验装置,实验研究了超导冷却系统热截流结构中,界面温度和接触压力对AlN块材与无氧铜(OFHC-Cu)块材间接触界面热阻的影响。在实验温度(90K-210K)和压力(0.273MPa-0.985MPa)条件下,AlN/OFHC-Cu接触界面热阻随接触压力的提高而降低,而当界面温度上升时界面热阻由于热载子热运动的强化而降低,温度较高时,接触界面热阻随压力变化的速率趋缓。低温下AlN/OFHC-Cu间的接触界面热阻是直接冷却超导系统的设计和超导系统的热稳定性方面必需解决的问题。

Experiment investigation on thermal interfacial resistance of AlN and OFHC-Cu Contact for applied HTS cryoclooer cooling

Aluminum nitride(AlN),which has fine thermal conductivity and super electrical insulation,is an important one of components in thermal intercept configuration of superconducting binary current lead.It is pointed that the influence of interfacial temperature and contact pressure on thermal interfacial resistance is experimentally studied by one-dimensional steady state heat conduction in cryogenic vacuum equipment for superconducting cryocooler cooling thermal intercept configuration.In range of temperature(90K-210K) and contact pressure(0.273MPa-0.985MPa),thermal interfacial resistance of AlN/OFHC-Cu decrease with a increase in contact pressure,and with a increase in interfacial temperature by the intensive movement of heat carrier.When the temperature is higher,the change rate of thermal interfacial resistance as contact pressure become more swift.It is important to study the thermal interfacial resistance of AlN/OFHC-Cu for the design of superconducting cryocooler cooling system and for thermal stability of superconducting system.