摘要
为研究接触热阻对瞬态平面热源(transient plane source,TPS)法测量高聚物薄膜热导率的影响规律以便提高测量准确度,阐述TPS法基本测量原理,根据串联热路中热阻的关系建立接触热阻的简化计算模型,以不同厚度硅橡胶薄膜为对象,通过回归分析的方法获得接触热阻随压力的变化规律,利用此规律测量单一厚度聚四氟乙烯薄膜和聚酯薄膜的热导率。结果表明:当未施加压力时,接触热阻的存在导致测量结果的相对误差为10%~30%,接触热阻会随压力的增大近似呈非线性关系减小,当压力达到200 k Pa时,可减小测量误差到6%以内。同种材质的高聚物薄膜还可通过改变厚度来减小接触热阻。
To study the effect law of contact thermal resistance on thermal conductivity measurement of high polymer films in TPS method and improve the measurement accuracy, this paper illustrates the basic measuring principle of TPS method and establishes the simplified calculation model of thermal contact resistance according to the relationship between thermal resistances of heat way in series. The law of the contact thermal resistance changing with pressure was obtained by the regression analysis method with silicone rubber films in different thickness. The thermal conductivity of PTFE film and polyester film in single thickness was measured in accordance with the law. The results show that the existence of thermal contact resistance brings about the relative error of 10%-30% when there is not load pressure, and when pressure increases, the thermal contact resistance decreases with nonlinear relationship. The measurement error can be decreased within 6% if the pressure is up to 200 kPa. For the same material of high polymer film, the thermal contact resistance can be decreased by changing the thickness of film.
出处
《中国测试》
CAS
北大核心
2018年第2期128-133,共6页
China Measurement & Test
关键词
瞬态平面热源法
接触热阻
高聚物薄膜
热导率
transient plane source method
contact thermal resistance
high polymer film
thermal conductivity
