This research focuses on the static mechanical, thermal and tribological properties of carbon fibre epoxy (CF/Ep) composites filled with boron nitride (BN) micro-filler powder (BN-CF/Ep). The mechanical properties studied were tensile, flexural, interlaminar shear strength and hardness. The thermal properties studied were dynamic mechanical and thermogravimetric analyses which were analysed through dynamic mechanical analyser and thermogravimetric analyser, respectively. The curing ability and dispersion of BN filler in the Ep and composites were investigated through differential scanning calorimetry, Fourier-transform infrared spectra and scanning electron microscopy. The tribological properties focused were three-body abrasion and dry sliding friction and wear conduct. Three-body abrasion tests were studied with silica sand of 212 µm particle size, 30 N load, 2.38 m s−1 sliding velocity and variable abrasive distances of 250 m, 500 m, 750 m and 1000 m. The dry sliding wear tests were performed using pin-on-disc (POD) wear experimental set-up with 60 N load, 3 m s−1 sliding velocity and variable sliding distances of 1000 m, 2000 m and 3000 m. The results followed the trend of BN1% > BN3% > BN5% composites in all mechanical properties. The carbon fabric reinforcement along with the BN-Ep matrix improved enormously all the mechanical properties except impact resistance. Further, it was exhibited that 1 wt% BN into CF/Ep prompts better mechanical properties with predominant damping capacity and thermal stability. Both the dry sand abrasive wear and POD test outcomes revealed that all BN-CF/Ep composites prompt predominant wear resistance. CF along with BN improves enormously the wear resistance with friction coefficient. Further, it was exhibited that 1 wt% BN into CF/Ep in both three-body abrasive and POD tests prompts better wear resistance. Generally speaking, it was presumed that BN-CF/Ep gracefully and successfully improved the mechanical, thermal and tribological properties and morphology of Ep for various mechanical, electrical components and load-bearing applications used in automotive and engineered applications.

The excellent specific strength of magnesium and its alloys makes them appealing for use in many engineering applications especially in the transportation industry. However, its use is restricted due to poor formability and wear resistance. Li addition enhances the formability of magnesium alloys while diminishing their strength. Equal channel angular pressing (ECAP) is one of the effective severe plastic deformation (SPD) methods that improves the strength by grain refinement thereby wear resistance. In this study, the effect of ECAP on the mechanical and wear behavior of Mg-4Li alloy is studied and correlated with grain refinement and microstructural features. The substantial grain refinement was obtained after three passes of ECAP and the sample was processed in the route BC displayed a minimum grain size of ∼9 µm. The ECAPed samples showed improved hardness and tensile properties and the sample ECAPed in the route BC displayed superior mechanical properties owing to its more refined microstructure. The microstructural features are analyzed using X-ray diffraction line profile analysis (XRDLPA) and correlated with the mechanical properties. The wear behavior viz. wear rate, coefficient of friction (COF) and roughness were investigated. It was demonstrated that the wear properties are improved after ECAP due to the refined microstructure and enhanced hardness and the obtained wear results are in good agreement with Archard’s wear law.

No abstract