Biomaterials play a significant role in revolutionizing human life in terms of implants and medical devices. These materials essentially need to be highly biocompatible and inert to the human physiological conditions. This paper provides an in-depth, critical and analytical review on the previous research work and studies conducted in the field of metals and alloys used as implant materials including stainless steel, titanium and its alloys, cobalt chromium and others. Since the manufacturing of medical implants relies on selected grades of biomaterials, metals play a significant role in biomaterials market. This paper focuses on highlighting some basic principles of manufacturing implant materials underlying composition, structure and properties of these materials. Finally, attention is also given to the role of these implant materials on the betterment of human life in terms of their failures by critically analysing these materials.

A microwave-assisted, environmentally friendly, high-yielding, time-saving synthesis of medicinally important 3-substituted isocoumarins was carried out in a single step by direct condensation of homophthalic acid with aryol and acyl chlorides under solvent-free conditions without any solid support. The synthesised isocoumarins were structurally characterised by microanalysis, 1H NMR, EI, IR and UV.

This research investigates the simultaneous sintering and surface nitriding of 316L stainless steel alloy using powder metallurgy method. The influence of sintering temperature and dwell time are investigated for maximum nitrogen absorption, densification and increased microhardness using response surface methodology (RSM). In this study, 316L stainless steel powder was compacted at 800 MPa and sintered at two different temperatures of 1150 and 1200 • C with varying dwell times of 1, 3, 5 and 8 h in nitrogen atmosphere. The sintered compacts were then characterized for their microstructure, densification, microhardness and nitrogen absorption. The results revealed that increased dwell time assisted nitrogen to diffuse into stainless steel matrix along with the creation of nitride layer onto the sample surface. The microhardness and density also increased with increasing dwell time. A densification of 7.575 g/cm 3 and microhardness of 235 HV were obtained for the samples sintered at 1200 • C temperature with 8 h dwell time. The simultaneous sintering and surface nitriding technique developed in this research work can help in improving corrosion resistance of this material and controlling leaching of metal ions for its potential use in biomedical applications.