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The present study deals with the effective usage of crab shell, which is a solid waste in the seafood industry. The crab shell was powdered and treated with chemicals to obtain the chemically treated crab shell powder. The crab shell was powdered and heated to the desired conditions to obtain thermally processed crab shell powder. These two powders so obtained were used with other ingredients in the development of brake pads. For comparison crab shell powder free brake pads were also developed. The developed brake pads were tested for various characteristics as per the industrial standards. Thermal stability was found using Thermogravimetric analysis. The fade and recovery behaviours were estimated for the developed brake pads using Chase test following IS2742 Part-4. The test results indicate that the thermally processed crab shell powder based brake pads showed better thermal stability with a char residue of 37%, while the chemically treated crab shell powder based brake pads had better fade and recovery characteristics with a fade rate of 1.71 % and recovery rate of 99.86 % due to its better heat dissipation and coarse structure. Scanning electron microscopy paved the way to study the worn characteristics of the Chase tested samples. An extensive evaluation method was used to rank the developed brake pads based on the Chase test performance; it also ranked chemically treated crab shell powder-based brake pads as the best performer.

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Fiber plays an important role in determining the hardness, strength, and dynamic mechanical properties of composite material. In the present work, enhancement of viscoelastic behaviour of hybrid phenolic composites has been synergistically investigated. Five different phenolic composites, namely, C1, C2, C3, C4, and C5, were fabricated by varying the weight percentage of basalt and aramid fiber, namely, 25, 20, 15, 10, and 5% by compensating with barium sulphate (BaSO4) to keep the combined reinforcement concentration at 25 wt%. Hardness was measured to examine the resistance of composites to indentation. The hardness of phenolic composites increased from 72.2 to 85.2 with increase in basalt fiber loading. Composite C1 (25 wt% fiber) is 1.2 times harder than composite C5. Compression test was conducted to find out compressive strength of phenolic composites and compressive strength increased with increase in fiber content. Dynamic mechanical analysis (DMA) was carried out to assess the temperature dependence mechanical properties in terms of storage modulus (E′), loss modulus (E′′), and damping factor (tan δ). The results indicate great improvement of E′ values and decrease in damping behaviour of composite upon fiber addition. Further X-ray powder diffraction (XRD) and energy-dispersive X-ray (EDX) analysis were employed to characterize the friction composites.