Thermal Conductivity Enhancement of Epoxy by Hybrid Particulate Fillers of Graphite and Silicon Carbide

Krishnamachar Srinivas^1*, Mysore Siddalingappa Bhagyashekar²

¹Department of Mechanical Engineering, Don Bosco Institute of Technology, Bangalore, India.
²Department of Mechanical Engineering, Raja Rajeshwari College of Engineering, Bangalore, India.

DOI: 10.4236/jmmce.2015.32010                

Abstract

This paper reports thermal conductivity studies carried out on room temperature cure (RT) epoxy resin (LY556 + HY951) containing three different particulate fillers such as Graphite (Gr) a soft material, Silicon carbide (SiC) a hard material and a hybrid graphite & silicon carbide (Gr-SiC). The weight fractions of three different fillers were varied from 10 wt% to 40 wt% in steps of 10%. Increased filler fraction increases the thermal conductivity of epoxy composites for all the three types of fillers. The results show that the synergic effect of hybrid filler (Gr-SiC) improves the thermal conductivity of epoxy composites compared to that of Graphite or Silicon carbide. The improvement in thermal conductivity for the epoxy hybrid composite containing 20% SiC, 20% Gr and 60% epoxy is 136% when compared with neat epoxy. Significant improvement in the thermal conductivity is observed for 40% filled epoxies. The experimental results were compared with analytical models such as Maxwell, Hashin, Hamilton-Crosser, Nielsen, and Cheng-Vachon. The predicted thermal conductivity by analytical models is in agreement with experimental results.

Keywords

Hybrid Composites, Particulate Epoxy Composite, Thermal Conductivity

Conflicts of Interest

The authors declare no conflicts of interest.

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