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Functionally graded materials (FGMs) are engineered materials that are inhomogeneous and can be purposefully processed to obtain discrete or continuously varying compositions/microstructures over a definable geometrical length. FGMs can be used in a number of applications, such as aircrafts, combustion nozzles, gas turbines, energy conversion cells, biomaterials, etc. The objective of this paper is to review the new developments in production processes and their prospects in the creation of next-generation FGMs. Traditionally, four potential methods were used for fabrications of FGMs, i.e. powder metallurgy, chemical vapor deposition, self-propagating high-temperature synthesis, and plasma spraying. Some of the recently developed methods are the cast-decant-cast process, friction stir processing, and laser-engineered net shaping, which are usually cost-effective and used to make a quiet change in properties. An effective production method for conversion of the concept of gradient into practice is still a challenge for the research community. In this paper, research works toward meeting these challenges will be highlighted, and the future scopes of investigation in this area will be explored.

Biomaterials play a major role in enhancing the quality, performance and longevity of human life. With the technological advancements in biomedical and material processing, quite a number of biomaterials are being synthesized with properties desirable for various biomedical applications. Among these, bioresorbable materials are the new class of Biomaterials. Bioresorbable materials can be used mainly in orthopaedic, cardiovascular, dental and tissue engineering applications. The potential bioresorbable materials identified were Magnesium alloys, Iron and Zinc alloys. However, there are certain issues with these bioresorbable materials for their application as implants. The current review presents the potential, physiological behavior and problems of Magnesium alloy. The biological performance of Magnesium alloys under different processing methods such as alloying, surface modification and bulk processing was discussed. This review may be a guide for new researchers to identify suitable processing method for Magnesium alloy. [ABSTRACT FROM AUTHOR]

Functionally graded cemented tungsten carbide belongs to a hybrid Functionally Graded Materials family. However synthesis of functionally graded cemented tungsten carbide is a great challenge due to possibility of "Co migration" and CaF2 vaporization during liquid phase sintering. Hence the present work deals with the development of nanocrystalline materials using ball milling and consolidation of milled material by Spark Plasma Sintering (SPS) for the preparation of functionally graded cemented tungsten carbide. The effects of ball milling and contents of Co, CaF2 and WC on WC/Co/ CaF2 powder mixture were analyzed. Grain morphology, particle size, micro-strain, crystallite size, etc. of milled samples were investigated using scanning electron microscopy and X-Ray diffraction techniques. In addition to that, density, microstructure, hardness, fracture toughness and residual stress of consolidated sample are also reported. These tests confirm the formation of nanocrystalline particles and sub-sequent consolidation of functionally graded cemented tungsten carbide with solid lubricant. Hence ball milling with SPS is a prominent and viable process combination for the preparation of functionally graded cemented tungsten carbide. [ABSTRACT FROM AUTHOR]