摘要
基于微结构低温工程学 ,提出三维低温界面层的概念 ,指出界面热阻是制冷机直接冷却超导磁体需要解决的关键技术之一。以GM制冷机为冷源 ,按稳态热流法原理测量了Bi 2 2 2 3、AlN的热导率及它们之间的低温界面热阻。在 0 15MPa～ 0 5 5MPa压力范围内 ,AlN和Bi 2 2 2 3间的界面热阻随界面层温度和接触压力的升高而降低 ,并随接触界面处温度的不同表现出不同的变化率。当界面层Bi 2 2 2 3侧温度为 5 5K时 ,在 0 5 469MPa的接触压力作用下 ,Bi 2 2 2 3和AlN间的界面热阻是厚度为 10mm的AlN垫片体积热阻的 3 8 86倍 ,是接触压力 0 2 2 81MPa时界面热阻的 3 8 7%。
The concept of three dimensional interfacial layer is presented based on micro nanocryogenics.It is pointed out that the thermal interface resistance(TIR)is one of the key technologies for superconductor cryocooler cooling.The thermal conductivity of Bi 2223 and AlN and the TIR of Bi 2223 to AlN contact were measured using axis steady heat flow method.The thermal interface conductance(TIC)of Bi 2223 to AlN contact decreases as the temperature and contact pressure (the contact pressure ranges from 0 15 to 0 55 MPa)increase.When the contact pressure is 0 5469 MPa and the Bi 2223 sied temperature is 55K,the TIR of Bi 2223 to AlN contact is 38 7% of the TIR under the contact pressure of 0 2281 MPa,and is 37 86 times larger than the thermal resistance of AlN spacer with a thickness of 10 mm.
出处
《低温工程》
CAS
CSCD
北大核心
2002年第5期12-16,共5页
Cryogenics
基金
国家自然科学基金资助项目
批准号 :510 760 13
