Saidatulakmar Shamsuddin

Effect of Sintering Temperature on Microstructure and Mechanical Properties of Ti-Nb-Sn-HA Composites Produced by Powder Metallurgy

The influence of difference sintering temperature: 900°C, 1000°C, 1100°C, 1200°C and 1300°C on the microstructure and mechanical properties of a biomedical Ti–35Nb-2.5Sn-15HA (wt.%) composite was investigated with regard to densification, porosity and hardness. Ti composite process was performed on elemental metal powders by blend the powder mixture at a rotating speed of 200 rpm mixing for 10 min and then sintered with difference temperature. The composites produced were then subjected to the following test: densification, Vickers micro hardness, microstructure by using SEM and X-ray diffraction analysis. Result indicated that the densification and Vickers micro hardness shown a decrease trend with the increasing of temperature due to the increasing trend of porosity up to 73%.

Influence of binder in iron matrix composites

The ability to use iron and its alloys as the matrix material in composite systems is of great importance because it is the most widely used metallic material with a variety of commercially available steel grades [1]. The aim of this study is to investigate the influence of binder in particulate iron based metal matrix composites. There are four types of binder that were used in this study; Stearic Acid, Gummi Arabisch, Polyvinyl alcohol 15000 MW and Polyvinyl alcohol 22000 MW. Six different weight percentage of each binder was prepared to produce the composite materials using powder metallurgy (P/M) route; consists of dry mixing, uniaxially compacting at 750 MPa and vacuum sintering at 1100° C for two hours. Their characterization included a study of density, porosity, hardness and microstructure. Results indicate that MMC was affected by the binder and stearic acid as a binder produced better properties of the composite.

Fabrication and Characterisation of Powder Metallurgy Fe-Cr Matrix Composites Reinforced with Al2O3

Abstract. Sintered powder metallurgy Fe based composites with advanced mechanical properties have been proposed as substitutes for more expensive cemented carbide and wrought alloys in many applications, especially as inexpensive wear resistance parts. The aim of this work was to fabricate and characterize a composite made of Fe-Cr as the matrix and Al2O3 particles as reinforcement. The composite was made by powder metallurgy method. The effect of different amount of binder, mixing duration, compaction pressure and sintering temperature has been investigated. Densification, micro hardness, wear resistance and compressive strength were used to characterize the composite. Powder metallurgy parameters that satisfy the composites quality have been optimized and result showed that higher sintering temperatures promote good sintering in the composites which produced better densification, higher reading of micro hardness, better wear resistance and compressive strength.

Solder microstructure and intermetallic interface evaluation between Sn-3.5Ag-1.0Cu-xNi lead free solder under long time thermal aging (x: 0, 0.05, 0.2, 0.5)

Sn-3.5Ag-1.0Cu-xNi (x: 0, 0.05, 0.2, 0.5) solder alloy has been developed to improve properties and microstructure of Sn-3.5Ag-1.0Cu based solder. The composite solder were synthesized via the powder metallurgy route which consist of blending, compacting and sintering process. The sintered solders were characterized for it melting temperature, SEM-EDX analysis was done to confirm the homogeneity of sample element distribution and X-Ray diffraction (XRD) analysis was conducted to see the presents of some phases. XRD analysis of sintered sample showed the presents of Ni3Sn4 and Ni3Sn2 phases. Solders were melted on copper substrate at 250°C for one minute on hot plate and aged at 150°C from 0 to 400 hours. The microstructure of the solder and the growth of IMC formation were studied under Scanning Electron Microscope (SEM) and EDX. The phases formed were studied under SEM-EDX. The SEM results show the presence of Cu6Sn5, Cu3Sn and Ag3Sn intermetallic in the Sn-3.5Ag-1.0Cu solder and Sn-3.5Ag-1.0Cu-xNi solder.

Dry sliding wear and compressive strength of Fe-Cr matrix composite with and without Al 2 O 3 reinforcement

Fe-Cr matrix composites reinforced with Al<inf>2</inf>O<inf>3</inf> particulates fabricated by powder metallurgy (PM) method offer potential for cheaper wear resistance materials and high temperature application. The influence of Al<inf>2</inf>O<inf>3</inf> amount on densification, micro-hardness, wear resistance and strength of the composites were evaluated. The results showed that Al<inf>2</inf>O<inf>3</inf> yield good influence on Fe-Cr matrix composites. Increases the amount of Al<inf>2</inf>O<inf>3</inf> to more than 5 wt% decreases composites relative density. The micro-hardness and wear resistance of the composites improved with increasing amount of Al<inf>2</inf>O<inf>3</inf> to 20 wt%. Beyond 10 wt% Al<inf>2</inf>O<inf>3</inf> addition, the strength properties began to decrease with an increase in Al“2”O<inf>3</inf> addition. Overall, the composites reinforced with 5 wt% Al<inf>2</inf>O<inf>3</inf> exhibited the best results.