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Since in the past decade ceramics were in the main concern than metals because of their higher hardness, thermal resistance, wear resistance and corrosion resistance. When wear resistance is required than Al₂O₃ is a good option.

Industrial applications of Al₂O₃ coatings in various fields, such as aerospace, marine and automobile sectors, are very vast due to their higher hardness value (~1200HV), a good wear resistance as well as corrosion resistance, chemical, thermal and mechanical stability. But these coatings also possess higher brittleness and porosity, which limits its further potential application. In order to minimize the porosity and brittleness accompanied with Al₂O₃ coatings, various second phase materials have been used as a reinforcement. Among various second phase materials, Titania (TiO₂) has been a common choice for the researchers due to their lower melting point than Al₂O₃. Hence, TiO₂ reinforced coatings have shown a lesser porosity and improved properties than monolithic Al₂O₃ coatings. Due to the lower melting point of TiO₂, when reinforced with Al₂O₃ it reduces the porosity and improvement in the mechanical properties of the plasma sprayed coatings because TiO₂ grabs Al₂O₃ grains and make coatings denser and increases wear resistance. So on increasing TiO₂ content leads to the densification of coatings and also increases wear resistance. On increasing the TiO₂ percentage in Al₂O₃ also improves the adhesion strength of the coatings, corrosion resistance and thermal shock resistance as compared to the composition of 3wt.% and 13wt.% TiO₂ in Al₂O₃. So that’s the reason we have taken Al₂O₃ - 40 wt.%TiO₂ in our study. Thermal spraying is one of the mostly used technique in the surface modification of the materials. Plasma spraying technique is one type of thermal spraying technique, in which impinging of molten or semi-molten particles on a grit blasted prepared substrate. These impinged particles solidify rapidly (~10⁶ k/s) and leads to splat. Integration of these splats makes coating. Microstructure of these coatings strongly depends upon the input power, feedstock materials, flowability of powder, secondary gas flow rate, standoff distance, transverse speed, carrier flow gas, powder feed rate etc. Density of the coatings directly depends upon the degree of melting and velocity of particles.

Nowadays, Al₂O₃ - 40 wt.%TiO₂ plasma sprayed coatings are widely used in automobile sector, aerospace sector, electronics sector, marine sector, power sector, etc. because of their excellent corrosion resistance, wear resistance, thermal shock resistance, low thermal expansion, high melting point and mechanical properties. Porosity is the major drawback of these plasma sprayed coatings that directly contributes lower fracture toughness, lower hardness value as compared to the bulk. Hence, wear and tribological behavior properties of these plasma sprayed coatings would be affected. To reduce the porosity of these plasma sprayed coatings, the reinforcement of carbonaceous material (GNPs) would be done because of their higher thermal conductivity, electrical conductivity, low density, higher tensile strength. GNPs possess higher modulus of elasticity (~1TPa), tensile strength of (~130GPa), higher thermally conductive and electrically conductive. Hence, with the reinforcement of GNPs in Al₂O₃ - 40 wt.%TiO₂ is highly suitable. But GNPs suffer few disadvantages also. Firstly, their high surface area can create agglomeration of GNPs because of their high surface energy and an agglomerate act as a defect in the composite and it will reduce the properties of the coatings. Secondly, these agglomerates can obstruction in the flow of the powder through the nozzle during plasma spraying. Thirdly, GNPs are carbonaceous material hence at high temp they are prone to damage. So, protection of GNPs during thermal spraying results in obtaining good microstructure of the coatings. With the reinforcement of GNPs in Al₂O₃ - 40 wt.%TiO₂, more degree of melting of the powder would happen because of the higher thermal conductivity of GNPs which circulates the heat to the whole matrix and that imparts densification of the coatings. Due to the densification of the coatings results in the improvement of mechanical and tribological behavior of coatings.

• Designing of chassis by using Inventor pro software.

• Strength calculations was done on ANSYS software.

• Fabrication of chassis using aluminium plate with a thickness of 5mm.

• For optimization of design parameters was done using Taguchi Method.

• Optimization of solar power for efficient usage.

• Fabrication of RC car.

• Final testing of RC car.