Characterization of graphite-chromium carbide composites manufactured by Spark Plasma Sintering.

Abstract

This manuscript contains an investigation about the influence of the chromium content on the properties of novel graphite-chromium composites obtained by spark plasma sintering (SPS), with great potential application in heat dissipation. Green compacts of 40 mm in diameter were first obtained by uniaxial pressing at 60 MPa, and then the composite was sintered at 1800°C in SPS under vacuum conditions and a pressure of 30 MPa. These sintering conditions involved local liquid phase, which promoted the densification of the composite up to values close to 90%. Different chromium contents were studied, 0, 1, 2, 5, 7 and 10 vol. %, where the best properties (densification, young modulus, electrical conductivity, thermal conductivity, and flexural strength) were obtained in the case of the composite with 7 vol. % Cr: 86.22%, 52.7 GPa, 0.79 MS/m, 264 W/m·K and 38.97 MPa, respectively, measured in the in-plane direction due to the anisotropic behavior of the composite.