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In this work, locally sourced non-hazardous materials were used to produce brake pad using grey relational analysis (GRA) and experimental design via central composite design. Raw materials selected for production include coconut shell, epoxy resin (binder), graphite (friction modifier) and aluminum oxide (abrasive). Twenty-seven samples were produced separately using coconut shell as reinforcement material by varying process parameters. Formulation of the brake pads samples was done using rule of mixture and a weight percent of 52% reinforcement material, 35% binder, 8% abrasive and 5% friction modifier were used for the production. Grey relational analysis (GRA) shows that optimal process performance can be obtained using molding pressure, molding temperature, curing time and heat treatment time of 14 MPa, 140 °C, 8 min and 5 h, respectively. Optimized sample was produced using the optimal set of process parameters obtained from GRA and compared with commercially available sample produced by Ibeto Group. The experimental results showed that the performance of the optimized coconut shell-reinforced brake pad compared satisfactorily with commercially available samples and capable of producing less brake noise and vibration during application. Analysis of variance shows that curing time with a contribution of 30.38% and 31.40% have the most significant effect on the hardness and ultimate tensile strength of the coconut shell-reinforced friction material, respectively, while heat treatment time with a contribution of 46.3% and 24.23% have the most significant effect on the wear rate and friction coefficient of coconut shell-reinforced brake pad, respectively. The effects of all the factors on the properties of the friction materials are significant since their p values are greater than 0.010 (1%). Keywords Brake pads • Central composite design • Grey relational analysis • Coconut shell and characterization List of symbols Axial value µ Coefficient of friction Distinguishing coefficient u Percentage weight δ Densities f Volume fraction X Weight F Applied load d Disk diameter t Time of exposure of specimen to abrasion N Radial speed b Support span (mm) t Specimen thickness (mm) Deflection (mm) w Specimen width (mm) χ Distinguishing coefficient n Number of factor level combination k Performance value MT Molding temperature MP Molding pressure CT Curing time HTT Heat treatment time

Red Balau saw dust was heat-treated at 180 C and 200 C for 1 h. Treated and untreated wood flour were compounded with LDPE at 9%, 20%, and 37% by weight and molded in an injection molding machine. Thermal and mechanical properties of the resultant composites were investigated as a function of filler loadings and treatment temperature. Thermogravimetric analysis revealed an increase in degradation peak temperature (T p ) of the heat-treated wood and composites. DSC revealed a decreasing trend in the degree of crystallinity (X c ) of the matrix when heat-treated wood was used as filler. On the other hand, untreated wood showed an increase in X c with increasing wood content. Tensile modulus increased with heat treatment and filler loading. Furthermore, flexural strength and modulus were found to increase with filler loading.

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