Low temperature thermal resistance for a new design of silver sinter heat exchanger
Low temperature thermal resistance for a new design of silver sinter heat exchanger
复制标题
银烧结换热器新设计的低温热阻
DOI：
10.1088/1742-6596/150/1/012037
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发表时间：
2008
期刊：
影响因子：
--
通讯作者：
W. Halperin
中科院分区：
文献类型：
--
作者：
J. Pollanen;H. Choi;J. Davis;B. T. Rolfs;W. Halperin
我们开发了一种新的程序，用于构建高表面积的银烧结热交换器。我们的配方在热交换器中加入了直径约为50微米的尼龙纤维和大量银的细线。为了增加热交换器内液氦的热导率，在烧结之前，尼龙纤维用有机酸溶解，留下通道网络。此外，银线增强了银烧结物的结构完整性，并降低了电阻。我们用这种热交换器制作了一个~ 3 He熔化曲线温度计（MCT），并在T = 2-150 mK的温度范围内测量了MCT内液态~ 3 He的热时间响应。我们发现在T ~ 1 mK时的热弛豫时间为~ 490 s。我们已经使用扫描电子显微镜（SEM）表征的热交换器和BET吸收测定的比表面积。
We have developed a novel procedure for constructing high surface area silver sinter heat exchangers. Our recipe incorporates nylon fibers having a diameter of ~ 50 microns and thin wires of bulk silver in the heat exchanger. In order to increase the thermal conductance of liquid helium within the heat exchanger, prior to sintering, the nylon fibers are dissolved with an organic acid leaving a network of channels. In addition, the silver wires reinforce the structural integrity, and reduce the resistance, of the silver sinter. We have constructed a 3-He melting curve thermometer (MCT) with this type of heat exchanger and measured the thermal time response of the liquid 3-He inside the MCT in the temperature range T = 2-150 mK. We find a thermal relaxation time of ~ 490 s at T ~ 1 mK. We have used scanning electron microscopy (SEM) to characterize the heat exchanger and BET absorption for determination of the specific surface area.