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The gradual phasing out of typical brake pad material led to the spark of extensive research in development of alternatives. Henceforth we have performed a tribological study to improve the performance characteristics of the friction product (brake pad) by using steel wool, a metallic material which has an excellent structural reinforcement property and high thermal stability which are indeed required to improve the performance of the brake pad. Under the study, five frictional composites were developed and optimized using the same ingredients in an appropriate proportion except steel wool (0%, 4%, 8%, 12%, and 16%) which is compensated by synthetic barite, and the synthesized compositions are designated as Na01 to Na05. The developed pads are tested for tribological behaviour under conventional environment in a standard pin on disc tribometer. It is observed that increase in steel wool concentration resulted in high coefficient of friction and low wear rate of pad as resulted in Na05 composition. SEM analysis of the wear surface has proved to be useful in understanding the wear behaviour of the composites.

Thermal conductivity and thermal stability plays a vital role on the performance of NAO brake pads . The Steel fiber a semi metallic composition is carried out in this paper to prepare the Non Asbestos Brake Pad. Steel fiber has good thermal stability and bulk density. So the optimization of steel fiber percentage for thermal behaviour is considered using TGA. The temperature rise during brake application will be between 150-4000C and this zone of temperature is very critical to determine the fade characteristics during friction testing. Less weight loss between 150 – 400°C during TGA testing means that it is a better thermally stable product. Hence, three different friction composites were developed with same formulation varying the steel fiber content with the inert filler namely barites and designated as NA01, NA02 and NA03 respectively. After the fabrication of the friction composites, the TGA test revealed that the composite NA01 had minimum weight loss during 160 - 4500C. The composites were then tested for Tribo performance using Constant speed testing machine following SAE J 661a standards. Thus we can correlate the thermal stability with the stability of friction based on minimum weight loss using TGA testing. Hence composite NA01 proved to be the best performer.On another aspect the NA01 has more rotor wear when compared to the other composition in that aspect of rotor wear NA03 is best.

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Performance of Non Asbestos brake pad requires the optimization of numerous criteria. Alumina fibre is a metallic material which is light weight, excellent wear resistance, thermal stability and structural reinforcement properties. Hence the present work deals with the development of three friction composites in the form of standard disc brake pads using same ingredients in same proportion except alumina fiber containing 7%wt, 11%wt & 14% wt which is compensated by synthetic barites (filler) containing 16%wt, 12%wt & 9% wt and designated as NA01, NA02 and NA03 respectively. Various physical, thermal and mechanical characterizations are carried out as per IS2742 Part 3 standards in which the loss of ignition decreased while the specific gravity, compressive strength and hardness increased with the fiber increase. Then the tribological properties (Fade and Recovery) are tested using Chase Test following IS2742 Part 4 standards. The fade μ and recovery μ % were significantly influenced by the amount of fibre combinations. It was proved that, increase in amount of alumina fibre % had significant effect on fade μ %.Thermo Gravimetric Analysis (TGA) proves that higher fiber content has more thermal stability leading to good fade resistance. Over all NA03 formulation is proved as superlative performer.