Thermal Characterization of Flax/Basalt Fiber Reinforced Phenol Resin Brake Pad Material: Effective Replacement of Asbestos

Asbestos fiber usage as reinforcement in friction material composites is avoided because of its carcinogenic property that might cause cancer. The aim of this study is to investigate the thermal characteristics of the novel noncommercial brake pad materials, i.e., flax fiber reinforced phenolic resin composites (FRPCs) and basalt fiber reinforced phenolic resin composites (BRPCs). FRPCs and BRPCs with different volume percentages of 2, 4, 6, and 8 of chemically treated flax and basalt fiber are fabricated by diffusion bonding technique. The thermal behavior was investigated by the use of differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) techniques. DSC results revealed that FRPC and BRPC samples reinforced with 6% volume fraction (Vf) of the respective fibers are having better thermal stability than other volume percentage, since the glass transition temperature (Tg) is relatively high. TGA analysis also shows that FRPC and BRPC specimens reinforced with 6% Vf of flax and basalt fibers have good thermal stability when compared to other volume fractions. The weight loss observed for 6% Vf of FRPC and BRPC is less compared to other specimens with increase in temperature. Scanning electron microscopy photography is used to analyze the orientation and bonding structure of matrix and fibers.