Large-scale preparation of thermal anisotropic macroscopic layered metallic materials by a mechanical rolling method

Abstract

The rapid development of modern miniaturized, portable, foldable electronic devices significantly raises the threshold for thermal management materials. Anisotropic thermal conductive materials are urgently required, which can dissipate redundant heat in the specific direction without affecting surrounding components. A critical challenge is to develop a suitable method for large-scale manufacturing highly anisotropic thermal conductive materials. Here, we proposed a new simple, efficient and low-cost mechanical rolling method for large-scale preparation of thermal anisotropic metal materials under conventional conditions. The bimetallic combination Ag/Al with comparative ductility and hardness was selected for repeated folding and calendering at room temperature. The maximum thermal anisotropic ratio of the metal plates reached up to 52.8. Interestingly, it was found that the addition of BN nanosheets can further enhance the thermal anisotropic ratio as large as three times. Our study provides a new simple idea for the synthesis of thermal anisotropic materials, which advances the development of thermal management materials powerfully.