The paper investigates the exceptional antiwear and extreme pressure properties of multiwalled carbon nanotube based mineral oil. Different samples of oil containing varying proportions of MWNT (MWNT) and graphite were prepared. The samples were tested for their antiwear and load bearing capacity according to ASTM G99 and ASTM D-2783 standards. After pass load test in four ball tester the rubbed surfaces were investigated with Scanning Electron Microscope (SEM) images. The wear test results show a decrease wear by 70-75% in case of multiwalled nanotube based mineral oil as compared with pure mineral oil. Furthermore, it has been observed that the load bearing capacity in case of multiwalled carbon nanotube based mineral oil increases by 20% as compared to pure mineral oil. A comparison in the antiwear and load bearing capacity properties of graphite and nanotube based mineral oil was studied which showed the inefficiency of graphite based lubricant over MWNT based oil. Thus, the finding would be helpful in developing new nanoparticle based lubricants.

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Stress shielding is known to cause bone refracture or cause low healing rate in fractured bones. The numerical study of bone healing process of a transverse fractured tibia was conducted in this research to reduce the stress shielding. The stress and strain on the callus were evaluated when bone plates of different metallic and non-metallic biomaterials were used. Time varying material properties of the callus were applied, and loading conditions were coupled with material properties of the callus. The strain distribution on the callus, and the maximum stress on the callus and bone plate were analysed. The analysis results shows that Polyether ether ketone/Nano-Hydroxyapatite/Short Carbon Fibre (PEEK/nano-HA/SCF) is most suitable for bone plating application for tibia. PEEK/nano-HA/SCF is chosen as it provides the optimum strain in the callus to promote bone healing. It has the closest stiffness to the cortical bone and hence stress shielding is minimized extensively. It has a uniform strain distribution at the fractured site for early bone healing process.