Possibility of Unusually High Thermal Conductivity Along Metal Ceramic Interfaces in the Aluminum-Spinel System

9610167拉杰本项目的重点是金属-陶瓷复合材料界面导热系数的测量。本研究集中在由纯铝基和镁铝尖晶石颗粒组成的颗粒复合材料的详细研究。这是因为初步证据表明，铝-尖晶石复合材料中的界面提高了复合材料的整体导热系数，这与复合材料界面降低导热系数的传统发现形成了鲜明对比。这项工作包括准备几个不同体积分数和不同颗粒大小的尖晶石样品。测量了这些样品的热扩散率，并仔细地表征了微观结构，以证实或否认沿铝-尖晶石界面存在异常热传导。这项研究是科罗拉多大学博尔德分校和弗吉尼亚州布莱克斯堡的弗吉尼亚理工学院合作进行的。如果这项探索性研究产生了积极的结果，那么将向基金会提交一份关于在原子水平上调查这一现象的定期建议。这种增强的导热效应可应用于许多具有重要商业价值的材料系统，如电子封装和多层器件。***

9610167 Raj The focus of this SGER project is the measurement of thermal conductivity of interfaces in metal-ceramic composites. The research concentrates on a detailed study of particulate composites consisting of a pure aluminum matrix dispersed with particles of magnesium aluminate spinel. This is motivated by preliminary evidence that interfaces in aluminum-spinel composites enhance the overall thermal conductivity of the composite, in stark contrast to the conventional finding that composite interfaces reduce thermal conductivity. The effort includes preparation of several specimens with different volume fractions and different particle sizes of spinel. The thermal diffusivities of these specimens are measured and the microstructure carefully characterized to confirm or refute the existence of an anomalous thermal conduction along the aluminum-spinel interface. The research is a collaboration between the University of Colorado at Boulder and Virginia Polytechnic Institute in Blacksburg, VA. If this exploratory research produces a positive result then a regular proposal to investigate the phenomenon at an atomistic level will be submitted to the Foundation. %%% This enhanced thermal conduction effect could be applied to many commercially important materials systems, such as electronic packaging and multilayer devices. ***