Syazuan Abdul Latip

The Effect of Carburizing Medium on Carbon Dispersion Layer of ASTM A516 Steel

Carburizing had been a renowned case hardening method for most metal which produced hard casing protecting the surface, resulting in improvement of the mechanical, wear and corrosion behaviour. Carburizing in solid medium offer low cost advantages, thus it is widely implemented. The objective of this study is to compare the carbon thickness layer formed after carburizing process at two different solid medium which is powder and paste form. ASTM A516 Grade 70 mild steel was use as the sample in this study. Carburizing process in both powder and paste medium are conducted at three different temperatures which are 850°C, 900°C and 950°C for 8 hours holding time and cooled in room temperature, for comparison purpose. The thickness layer observation and measurement was carried out using optical microscope and XRD analysis was also conducted to validate the carbon appearances. Rockwell hardness test was also performed before and after carburizing process. The findings from this study indicated that paste carburized samples induced deeper carbon diffusion compared to powder carburized samples. Higher carburizing temperature is also favorable in enhancing the thickness layer in both powder and paste carburized samples. It could be stated that comparable thickness layer could be achieve faster in paste carburized samples, compared to powder carburized samples, which can lead a more cost effective carburizing process.

Storage Modulus Analysis of Kenaf Fibre Reinforced Epoxy Composites

This article presents the storage modulus analysis of kenaf fibre composites that reinforced by two different epoxy matrix systems, named epoxy A and epoxy B. These epoxies are commercially available in Malaysia and been used as a polymer matrix in composite research. Composites were made from hand lay out technique and undergo storage modulus evaluation by using dynamic mechanical analysis (DMA). Fibre content ratios were found to affect the storage capacity in both reinforced epoxy system. However, the addition of 45% kenaf fibre volume ratios reinforced into Epoxy A composites exhibits only week improvement as compared to its rival. The possibility of causes might be attributed to the week interfacial between fibre and matrix.

Boron Dispersion Layer of Paste Boronized 304 Stainless Steel before and after Shot Blasting Process

Boronizing had been extensively used in enhancing the properties of metallic material such as steel by formation of hard casing on the surface of the substrate. This study highlighted the effect of applying surface deformation process which is shot blasting on the dispersion layer of paste boronized 304 stainless steel. Boronizing treatment was conducted using two different temperatures which are 850°C and 950°C for 6 hour holding time. Shot blasting process was conducted onto the surface of the samples before boronizing process in order to allow deeper boron dispersion layer. Microstructure and boron dispersion layer measurement were then accomplished using optical microscope. XRD analysis was performed to validate the existence of Fe2B phases and Rockwell hardness test was also conducted to obtain the hardness values. The results indicated that combinations of high boronizing temperature and shot blasting process facilitate deeper dispersion layer. Deeper dispersion layer are paramount as it will enhanced the hardness and wear properties.

Performance and Emissions of Jatropha-Palm Blended Biodiesel

This paper deals with performances and emissions of Jatropha-Palm blended biodiesel as fuel for 4-stroke single vertical cylinder diesel engine. Five fuel samples were tested; i) Diesel fuel supplied by Petronas (PDF); ii) 5% of blended Jatropha-Palm biodiesel and 95% Diesel fuel (B5JPB); iii) 10% of blended Jatropha-Palm biodiesel and 90% Diesel fuel (B10JPB); iv) 15% of blended Jatropha-Palm biodiesel and 85% Diesel fuel (B15JPB); and v) 20% of blended Jatropha-Palm biodiesel and 80% Diesel fuel (B20JPB). Engine performances (specific fuel consumption, brake thermal efficiency) and emissions (exhaust gas temperature and Nox emission) were analyzed and have been discussed in this study. All tests were carried out at varied load conditions which were 0.13, 0.15, 0.17, 0.19 and 0.21 kW. The results revealed that B10JPB blended showed better engine performances compared to its other blends and comparable performances compared to PDF. Comparable Nox emitted of all Jatropha-Palm fuel blended biodiesel fuel sample has been demonstrated to those PDF.

Mechanical properties of tempered Ti-Nb alloyed ductile iron

The applications of ductile iron in numerous engineering applications require continuous effort in properties enhancement due to the necessity of product sustainability and performance. The studies highlighted the effect of 0.5 wt% titanium and niobium addition the mechanical properties of tempered ductile iron. The samples were prepared through conventional CO2 sand casting process. Heat treatment was conducted by austenitizing at 900°C for 1 hour and subsequently oil quenching before tempered at three different temperatures which are 500°C, 600°C and 700°C at 1 hour holding time. The mechanical properties were evaluated through impact (ASTM E23) and hardness (Rockwell) test. Microstructure observation and XRD analysis was also performed on as cast and tempered samples. The findings indicated that increasing the tempering temperature at 700°C enhanced the hardness and tensile strength of tempered alloyed ductile iron compared to other samples. The enhancement of the mechanical properties of tempered alloyed ductile iron is expected to further expand the applications of ductile iron.

Corrosion behavior of 0.02–2.0wt% Vanadium alloyed grey iron

This paper focused on corrosion behavior of grey cast iron having 0.02wt %, 0.5wt% and 2wt% vanadium as the alloying elements. Vanadium alloyed grey cast iron samples were produced by using Y - block CO2 sand casting process and poured into double cylinder mould. The corrosion behavior was measured from polarization method, under 3.5% NaCl aqueous solution, conducted at room temperature. The corroded surfaces were then observed through scanning electron microscopy (SEM) and the compositions were obtained through sparked EDX analyzer. The microstructure vanadium alloyed grey cast iron show the presences of graphite flakes surrounded by ferritic structures. The corrosion rate, which was obtained from polarization test indicated that 2% alloyed grey cast iron produced better corrosion resistance compared with 0.02% and 0.5% vanadium alloyed grey cast iron.

Dynamic characterization of fiber glass reinforced epoxy plate using OMA for damage detection

Composite materials with nonlinear properties are proned to subsurface damages such as core crack, delamination, etc., that are difficult to detect visually. Even though vibration response as damage detection method is widely used in engineering applications, its usage is to nonlinear and nonhomogenous properties especially in composite materials is still limited. This paper attempts to apply vibration based damage detection method specifically operational modal analysis (OMA) on fiber glass reinforced epoxy plate. OMA is used on undamaged fiber glass reinforced epoxy plate to extract the dynamic parameters and after which the procedure is extended to damage fiber glass reinforced epoxy plate. Both and damaged composite material are tested for different boundary conditions i.e. free-free on 4 edges, 1 edge clamped, 2 edges clamped, 3 edges clamped and 4 edges clamped condition. Results of these experimental setups will be compared to establish modal parameters on undamaged and damaged composites plate.