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Metal Injection Molding (MIM) is a cost-effective technique for producing small, complex, precision parts in high volumes. MIM consists of four main processing steps: mixing, injection molding, debinding and sintering. In the mixing step, the powder titanium alloy (Ti6Al4V) medical grade is mixed with a binder system based on palm stearin to form a homogeneous feedstock. The rheological studies of the feedstock have been determined properly in order to success during injection into injection molding machine. After molding, the binder holds the particles in place. The binder systems then have to be removed completely through debinding step. Any contamination of the binder systems will affect the final properties of the parts. During debinding step, solvent extraction debinding has been used to remove partly of the binder systems. The debound part is then sintered at high temperature under control atmosphere furnace. The properties of the sintered craniofacial implants then was measured and compared. The sintered craniofacial implants also then were determined in term of in-vitro cytotoxicity study using mouse fibroblast lines L-929. The results show that the sintered craniofacial implants of titanium alloy produced by MIM fullfill the in-vitro cytotoxicity test.

The most demanding high temperature application requires nickel-based super alloys, named Inconel 718 (IN718) is a precipitation hardenable nickel chromium alloy containing significant amount of iron, niobium and molybdenum along with lesser amounts of aluminium and titanium. The development of IN718 for metal injection molding was already proposed to provide increased resistance to distortion during and prior to debinding. This paper reports on the effects of sintering temperature on physical and mechanical properties of IN718 alloy. IN718 powder (60 vol%) with binder formulation (40 vol%) consists of polyethylene (PE) and palm stearin (PS) were mixed homogeneously and injected to produce green compacts. The binders then was removed and sintered at 1100 °C and 1200 °C for 8 h respectively. During sintering, the debound part is heated, which is allowing densification of the powder into a dense solid followed by elimination of pores. The sample sintered in vacuum condition at atmosphere 10-5 mbar whereby samples sintered at 1100 °C, show the density of 6.806 g/cm3 compared to samples sintered at 1200 °C is 8.186 g/cm3. Super alloy sintered at 1200 °C exhibited better densification rate with lower porosity. The preliminary results indicate that super alloy can be used in the MIM fabrication of nickel based super alloys to produce high-density sintered parts.

Stainless Steel materials (SS316L) generally known as a highly wear performance and resistant to corrosion. The purpose in this study is to produce the stainless steel foam and physical properties of sintered 316L stainless steel materials produced by powder metallurgy (P/M) method. In this paper, the method is based on using spherical urea as space holder was investigated. Then, the foams will be given to consider the properties of SS316L foam after sintering process. Powder metallurgy process needs to go through the mixing, pressing, sintering and analysis. The selected compositions of SS316L were varied from 50 wt % to 60 wt % SS316L, respectively while the remaining percentages are foaming agent. The SS316L powders were cold-pressed with 8 tons pressure and sintered at 1200°C via tube furnace. The SS316L foams were then characterised using Scanning Electron Microscopy (SEM) for morphological characterisation of the samples after sintering process. Lastly, porosity and density were tested for this sample. As a result, the composition with 60 wt % SS316L is provided higher bulk density and lower porosity which are 4.34 g/cm3 and 69.03 %, respectively.