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Feedstock preparation is one of the most crucial steps that will influence the metal injection molding process. In this study, the properties of Cu and space holder powder were determined. Powder morphology was captured using Scanning Electron Microscopy (SEM). Three different ratios of feedstocks were premixed with potassium carbonate as space holder using Turbulence Shaker mixer prior to mixing with constant binder system consist of waste rubber (WR). Mixes of three feedstocks with from 40, 50 and 60 wt. % were carried out in Brabender Plasticoder. All feedstocks were mixed at constant powder loading. The feedstocks were successfully injection molded using Vertical Injection Molding machine at 200°C.

CoCrMo alloy is one of the most used metallic biomaterials due to its high wear. Premature wear of the component is one of the main cause of hip prosthesis failure. The objective in this study is to investigate the tribology properties of sintered CoCrMo fabricated via injection moulding. Tests were carried out at room temperature comparing metal injection moulded dog bone tensile samples at different sintering temperatures. The parameter used for the pin on disk test is a 10kN load, 500m sliding distance and a chromium steel ball as a sliding partner. The morphologies and compositions of the worn surfaces were analysed by optical and scanning electron microscope. The results showed that the wear mechanism and friction coefficient of CoCrMo depended strongly on the microstructure which was influenced by the sintering temperature.

Carbon(C)/Copper(Cu) Composites based materials were developed by associating both pressure and heat to the mixture of the powder. Three samples of different formulations were prepared by the powder metallurgy route in which the C-Cu powder were mixed with E-poxy Resin in a tubular mixer, pre-compacted using an automated hydraulic press machine, warm compacted using a warm compaction machine and finally post baked in oven. Each sample was subjected to density, hardness, transverse rupture strength and resistivity tests. The microstructures of the sample were observed under the scanning electron microscope. Test results of the developed samples show that sample C produced the highest physical, mechanical and electrical properties. However, the samples developed had lower physical, mechanical and electrical properties as compared with the commercial sample. This phenomenon was taught to be due to high porosity and insolubility of carbon and copper in the sample developed. Thus, father study will be done based on sample C formulation.

Cobalt-chromium alloys are commonly used for surgical implants because of their high strength, superior corrosion resistance, non-magnetic behavior, and biocompatibility. Cobalt-Chromium-Molybdenum (Co-Cr-Mo) applications include prosthetic replacements of hips. This paper presents the attempt to produce metallic implant using Co-Cr-Mo powder by MIM process, focusing on the effects of different heating rate during sintering process at 1380°C. Co-Cr-Mo powder were mixed homogeneously with palm oil and conventional binders respectively with powder loading 65 vol% and was injection molded using vertical injection molding machine with the nozzle temperature of 160°C to produce green compacts. The binders then was removed by solvent extraction process and sintered in vacuum condition at atmosphere 10-5 mbar at temperature 1380 °C with varied heating rate; 0.5°C/min, 1.0°C/min and 3.0°C/min . Results indicated that sintered density and tensile strength varied from 8.100 gcm-3 to 8.200 gcm-3 and 546.971 MPa to 798.767 MPa respectively. The mechanical properties comply with the international standard (ASTM F75).

Gold nanoparticles (Au NPs) have potential applications in catalysis, drug delivery, sensors and environmental remediation. This wide range application is due to its amenability of synthesis and functionalization, less toxicity and ease of detection. The present work focuses on functionalization of Au NPs with chitosan for further application in biomedical research. Gold nanoparticles (Au NPs) functionalized chitosan were prepared by reducing gold salt solution at various pH medium in the presence of sodium borohydride. The effect of pH and chitosan concentration on the Au particle size and distribution are studied. The results revealed the dependence of Au particle size on the pH of the solution. The smallest Au particle size is found to form in a range of 10.22 ± 2.96 nm at 0.2% chitosan concentration. In this study, we anticipate the Au NPs functionalized chitosan can be used for drug delivery applications.

Powder injection molding (PIM) is a powder metallurgy process currently used for the production of complicated and near net shape parts of high performance materials [. This technique basically combines the advantages of plastic injection molding and the versatility of the conventional powder metallurgy technique. The process overcomes the shape limitation of powder compaction, the cost of machining, the productivity limits of isostatic pressing and slip casting, and the defect and tolerance limitations of conventional casting [1, 2, . According to German and Bose [, the technology of metal injection molding (MIM) is more complicated than that of the plastic injection molding, which arises from the need to remove the binder and to densify and strengthen the part. The process composed of four sequential steps: mixing of the powder and organic binder, injection molding, debinding where all binders are removed and sintering [1, 2, 3, 4]. If it necessary, secondary operations such as heat treatments after sintering can be performed [1, 2, 3, 4, .