Preparation and Properties of Glass Fiber Reinforced Carbon Foam Composites

The paper presents a novel kind of carbon foam composites reinforced by chopped glass fibers. Microstructure, mechanical properties and thermal insulation of the composites have been investigated by scanning electron microscopy, universal testing machine and laser thermal constant analyzer, respectively. Results showed that carbon foam composites had a spherical and closed-cell structure; chopped glass fibers were uniformly distributed in the carbon matrix along different directions. The mechanical properties exhibited optimum with the 7% glass fiber additives, 11.27 MPa of shear strength, higher than that of pure carbon foams by as much as 111%. Compressive and shear fracture were both characterized by gradient brittleness. Many tiny open-pores existed in carbon foams with a certain amount of glass fiber additives, giving rise to the higher thermal conductivity. Nevertheless, carbon foam composites possessed good thermal insulation, 0.311 W·m⁻¹·K⁻¹ at room temperature, and 1.04 W·m⁻¹·K⁻¹ in 800 °C at the most.