Investigation and development of polymer-based composite material properties for high temperature industrial wheel applications

In this study, the effects of glass fiber and graphite additive rates on novalac based phenolic resin were investigated. The physical and mechanical properties of the produced materials, as well as their thermal decomposition and combustion resistance, were also examined. In addition, the effect of the combined effect of glass fiber and graphite particles in the novolac matrix was investigated. Samples containing glass fiber and graphite in different rates will be prepared. In the characterization process of the produced composite samples; porosity and density(Archimedes' method) to determine of physical properties, hardness, tensile and flexural tests to determine of mechanical properties, thermogravimetric analysis (TGA) to determine thermal properties, scanning electron microscopy (SEM-EDS) for morphology of matrix and additive particles, microstructure of hybrid composite powders characterization of fracture surfaces, and limit oxygen index (LOI) tests to determine flame retardance properties were applied. According to the obtained thermogravimetric datas, it was observed that the decomposition temperature increased while the amount of decomposed mass decreased thanks to the glass fiber and graphite particles added to the novolac resin. While the hardness, maximum tensile and flexural strengths of pure novalac material were 32 HRM, 12 Mpa and 20.3 Mpa, respectively, the optimum composite sample (30% glass fiber, 40% graphite) was determined as 98 HRM, 33.8 Mpa and 77.4 Mpa. While the LOI value of the pure novalak material was 37%, high flame retardancy was determined with an increase of up to >50% among the composite materials produced.