Thermal Conductivity of Composite Materials Copper-Fullerene Soot.

Tatiana Koltsova,Tatiana Larionova,Olga Klimova-Korsmik,Elizaveta Bobrynina,Aleksei Vozniakovskii

doi:10.3390/ma15041415

Abstract

Copper-based composites strengthened with fullerene soot nanoparticles of 20–30 nm size in concentration up to 23 vol.% were prepared via two methods: mechanical mixing and molecular level mixing. The dependence of thermal conductivity on the carbon concentration was studied. Maxwell’s model describes well the change in the thermal conductivity of the composite obtained by molecular level mixing. However, thermal conductivity of the composite produced by mechanical mixing is significantly lower than the calculated values, due to structural inhomogeneity and residual stresses. Comparison of the thermal conductivity of Cu-fullerene soot composites with that of Cu-based composites described in the literature showed that the prepared materials are not inferior in thermal conductivity to composites containing carbon nanotubes, despite the fact that fullerene soot has a much lower thermal conductivity.

Highlights

Copper is a common and economical material with high conductivity, but at the same time pure copper is considered a low strength material
In previous works [10,11], we showed the possibility of obtaining composite materials of the Cu-fullerene soot (FS) system with physical and mechanical characteristics at the level of copper-carbon nanotubes (CNTs) materials
The relative density of the samples prepared via mechanical milling (MM) was 90.5–96.0%, and that of the samples prepared by molecular level mixing (MLM) was 97.0–98.5%

Summary

Introduction

Copper is a common and economical material with high conductivity, but at the same time pure copper is considered a low strength material. With the addition of CNTs into a copper matrix, an increase in strength characteristics and conductivity is expected, but the overall thermal conductivity of copper-nanocarbon materials can even be reduced due to random orientation of CNTs, high interfacial resistance at the copper-CNT interface, porosity, agglomeration of nanostructures and other negative factors [2,3,4,5]. In this regard, the method of adding carbon nanostructures and the method of compaction of the composite material significantly affect the thermal conductivity of composites. With an increase in the content of CNTs, the authors attribute the decrease in thermal conductivity to an increase in the number of copper-CNT contacts and a thermal barrier at the phase interface

Methods

Results

Conclusion