Composite material based on an ablative phenolic resin and carbon fibers

Abstract

In this study, a technological procedure for the production of a molding compound based on short carbon fibers and an ablative phenol-formaldehyde resin for high temperature application was optimized. The starting raw materials were characterized and molding compounds with different fiber/ /matrix ratios and different fiber lengths were obtained. From the different laboratory samples, molded parts were made by thermo-compression. The basic mechanical and thermal properties of the composites were determined. From the obtained results, the optimal fiber/matrix ratio was determined for a production of molding compound for high temperature application. The molding process of the composite material was optimized and all the parameters for good mechanical properties and high thermal stability of the composite were obtained. Optimization of the composite molding process was performed by the application of a numerical method for a planned experiment, i.e., a full three-factorial experimental design with variance of all three parameters (fiber length, temperature and time of the press cycle) on two levels. The obtained mechanical properties (flexural strength: 247 MPa, modulus: 27.6 GPa, impact resistance: 110 (for test moldings 10 mm?10 mm) and 91 kJ/m2 (for test moldings 15 mm?15 mm)) justified the application of this composite material in the automotive, leisure, military and other industries where high temperature resistance and high mechanical strength is required.