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Powder Metallurgy (PM) deals with products and processes which use raw material in the form of powders that are compacted into the required shape and size using suitable moulds. These compacted powders are called "Green Compacts". The properties of the component produced by PM processes are influenced by powder characteristics such as composition, morphology, particle size, distribution, and method of compaction. The first step in PM process is preparation of "green" compacts. Uni-axial pressing is one of the most widely used compaction method for the preparation of green compacts. The process is characterized by three distinct phases namely re-arrangement of powder particles, inter-particle sliding and plastic deformation of powder particles.In this paper the effect of metal powder composition, particle morphology on "green" density under uni-axial pressing is presented. Iron powders with average particle size in the range of 2 to 150 microns show a linear relationship between green density and pressure. Green densities greater than 75% can be achieved with a pressure of 500 MPa. Micron size aluminum, nickel, titanium cobalt and iron powders were compacted under 200 MPa pressure to evaluate the effect of composition. Aluminum had the highest green density of 90%, followed by nickel at 75%, titanium at 65% and iron, cobalt at 55%. The three distinct phases of powder densification, mentioned earlier, were clearly observed in the porosity versus pressure plots for all the powders.

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Silicon carbide (SiC) and Molybdenum disulphide (MoS2) has been expected broad contemplation is a potential strengthening particulate for metal matrix composites (MMCs) to enhance the mechanical and wear behaviors. The purpose of this study is to process and investigate the mechanical characteristics of LM 24/SiC/MoS2 composites. These composites were fabricated via the stir casting process from the prepared arrangements of LM 24/SiC/MoS2 with various weight proportions. The following proportions are pure LM 24, LM24-3wt.%SiC-1wt.%MoS2, LM24-6wt.%SiC-1wt.%MoS2 and LM24-9wt.%SiC-1wt.%MoS2. The scanning electron microscope (SEM) utilized to inspect the micrographs on processed composites. The SEM micrographs interpret identical dispersion of SiC with LM 24. The influence of SiC weight percentage on the physical properties like density, relative density & porosity and mechanical properties like tensile, compression, hardness, impact and flexural strength and tribological behavior were investigated. The processed LM24-9wt.%SiC-1wt.%MoS2 composites compose the enhanced mechanical properties. The wear performance was studied throughout the pin on disc device with various wear process parameters. These parameters are load, Sliding velocity and distance. Finally, these parameters are framed via the L16 orthogonal array and to attain the minimum wear rate and coefficient of friction from the optimal process parameters by Grey Relational Analysis (GRA). The optimal parameters for wear rate and coefficient of friction are LM24-9wt.%SiC-1wt.%MoS2 and followed by the wear parameters namely load 15N, sliding velocity 2 m/s and sliding distance 1600 m, respectively. The ANOVA outcomes uncovers that the load is the most significant parameter for wear rate and coefficient of friction.