Method and apparatus for measuring thermal conductivity

Abstract

The invention provides a method for measuring the thermal conductivity. The method includes steps: S1) placing a to-be-measured sample at one end of a reference material, wherein the initial temperature of the to-be-measured sample is T0; S2) heating one end, not in contact with the reference material, of the to-be-measured sample, wherein the heating temperature is Tf; S3) monitoring the change of the temperature of a contact position of the to-be-measured sample and the reference material, recording a time required by increase from a certain temperature T1 to the other temperature T2 (T0<=T1<=T2<=Tf) as deltat, and obtaining the thermal conductivity of the to-be-measured sample according to deltat, the thickness of the to-be-measured sample, the thermal diffusivity of the reference material, and the thermal conductivity of the reference material. Compared with the prior art, according to the method, the increase rate of a temperature field is quantified by employing the reference material of a known property to restore the thermal property of the to-be-measured sample so that the method can be used for measuring the to-be-measured sample with small dimension (millimeter and submillimeter scales) and measuring the thermal conductivity of the to-be-measured sample with other unknown properties including density and thermal capacity etc., the preparation measuring method is simple, special processing of the to-be-measured sample is avoided, and the cost is low. 本发明提供了一种测量热导率的方法，包括：S1)将待测样品放置于参考材料的一端，待测样品的初始温度为T0；S2)加热待测样品不与参考材料接触的一端，加热的温度为Tf；S3)监测待测样品与参考材料相接触位置温度的变化，记录从某一温度T1增加到另一温度T2(T0≤T1＜T2≤Tf)所需的时间为Δt；根据Δt、待测样品的厚度、参考材料的热扩散率及参考材料的热导率得到待测样品的热导率。与现有技术相比，本发明利用已知性质的参考材料量化温度场的增加速率，以还原待测样品的热性质，因此本发明可用于测量具有小尺寸(毫米及亚毫米级)的待测样品，还可用以测量未知其他性质如密度和热容量的待测样品的热导率，且制备测量方法简单，待测样品无需经特殊处理，成本较低。