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Mohd Ridzuan Mohd Jamir
Preferred name
Mohd Ridzuan Mohd Jamir
Official Name
Mohd Ridzuan , Mohd Jamir
Alternative Name
Ridzuan Mohd Jamir, Mohd
M Ridzuan, M. J.
Ridzuan, M. J.M.
Mohd Jamir, Mohd Ridzuan
Jamir, Mohd Ridzuan Mohd
Main Affiliation
Scopus Author ID
36069815000
Researcher ID
H-9343-2012
Now showing
1 - 10 of 47
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PublicationDynamic mechanical analysis of graphene nanoplatelets/glass reinforced epoxy composite( 2021-10-25)
;Ahmad M.A.A. ; ; ;Sulaiman M.H.This paper presents a study on dynamic mechanical analysis (DMA) of graphene nanoplatelets (GNPs)/glass reinforced epoxy composite. The composite was fabricated by a hand lay-up technique followed by vacuum bagging technique. GNPs weight fraction was 0.5 and 1.5 wt.% for a fixed glass fibre fraction. The test was carried out in terms of storage modulus (E’), loss modulus (E”), and tan δ. The result indicates that 1.5 wt.% GNPs/glass reinforced epoxy composite obtain the maximum value of the dynamic mechanical properties due to the incorporation of GNPs nanofiller. The improved dynamic mechanical properties were related to better interfacial interaction of the nanofiller with the epoxy matrix. The glass transition temperature (Tg) value for 0.5 and 1.5 wt.% GNPs/glass were 62.84 and 66.01 °C, respectively. -
PublicationEnergy absorption and failure behavior of Al/CFRP/GFRP hybrid tubes under quasi-static axial loading( 2023-07-01)
; ; ; ;Fiber metal laminate (FML) is gaining increased interest among researchers in designing thin-walled tubes as an efficient energy absorber. The combination of aluminum tube and fiber-reinforced polymer (FRP) as an FML hybrid tube has successfully demonstrated enhanced crashworthiness performance of structures. Previous studies reported FML hybrid tubes employing a single type of FRP composite material as the laminate material. Investigations on the effect of stacking sequences of multiple types of FRP composite as laminate materials are limited and mostly focused on sandwich structures. This study aims to investigate the effect of reinforcement material as a laminate layer and stacking sequences on the crashworthiness characteristics of aluminum-FRP hybrid tubes under quasi-static axial compression loading. The crashworthiness characteristics and the failure behavior of aluminum monolithic tube, aluminum-single FRP material, and aluminum-multi FRP material hybrid tubes are tested and compared. Glass FRP (GFRP) demonstrates great potential as a laminate material for aluminum tube compared with carbon FRP (CFRP). Aluminum-GFRP and aluminum-GFRP-CFRP hybrid tubes exhibit a 26.4 % and 66.9 % increase in energy absorbed, respectively, compared with the monolithic aluminum tube. The specific energy absorption and crushing force efficiency of the aluminum-GFRP-CFRP hybrid tube show minimal reductions of 4.9 % and 6.2 %, respectively. GFRP is the better choice of laminate material for aluminum tubes compared with CFRP. Multiple FRP laminates show a larger crashworthiness enhancement of FRP hybrid tubes in achieving better crashworthiness performance of the energy absorber. These findings imply that the selection and stacking sequences of laminate material are vital in tailoring the performance of the hybrid tubes toward efficient energy absorbers.47 3 -
PublicationMorphological and optical properties of porous hydroxyapatite/cornstarch (HAp/Cs) composites( 2020-01-01)
;Beh C.Y. ; ; ;Mohd Tarmizi E.Z. ;Eng S.K. ; ; ;Ahmad Saad F.S.This paper presents the correlation between the morphological characteristics and the diffuse reflectance (optical properties) of the porous hydroxyapatite/cornstarch (HAp/Cs) composites with various starch proportions (30, 40, 50, 60, 70, 80 and 90 wt%). The porous composites were measured via SEM and enhanced by image processing to find the average pore size, strut width, and average surface roughness. The average porosity of the porous composites was measured using liquid displacement method. The diffuse reflectance spectroscopy was implemented to investigate the diffuse reflectance and the corresponding optical band gap energy of the porous composites in the 500e900 nm range. A relationship between morphological characteristics and diffuse reflectance properties were established using Pearson's correlation coefficient. The findings of the study depict that a strong correlation can be noticed between optical band gap energy with porosity, pore sizes and surface roughness of the porous composites. Meanwhile, the strong correlations between the diffuse reflectance spectral gradient with surface roughness can be observed. The moderate correlations can be observed between the diffuse reflectance spectral gradient with pore sizes and strut width of the porous composites.2 -
PublicationA study on the significance of exhaust manifold’s bending angle to the brake torque of 115cc SI engine( 2023-01-01)
;Murali R. ; ; ; ;Azizul A.I. ;Rani M.F.H. ; ;Sunan S. ;Ali M.H.A. ;Ramasamy G.Hisham M.H.N.The exhaust manifold is a crucial component of the exhaust system in any SI engine, responsible for efficiently expelling combustion products. However, when the exhaust manifold's design is suboptimal, it leads to negative consequences for the engine's performance due to the presence of backpressure. Backpressure refers to the difference between maximum exhaust pressure and atmospheric pressure. An increase in backpressure decreases the overall performance and fuel efficiency of an SI engine. This study aimed to investigate the bending angle characteristics of the exhaust manifold and the brake torque of the 115cc SI engine using 1D engine analysis. The relationship between the exhaust manifold's bending angle characteristics and the brake torque was analysed using Analysis of Variance (ANOVA) with a p-value of less than 0.05, while the validation with experimental data showed a maximum error of 6.62. In the previous research, it was noted that a lower bending angle leads to better performance. However, the current results indicate that out of the three bending angles considered, having one of them yields the most substantial enhancement in brake torque. The optimized bending angle configuration obtained from the analysis increased the mean brake torque by 0.011 Nm (0.14%). Consequently, this study enhances the average brake torque through the optimal bending angle characteristics of the exhaust manifold. The study's objective aligns with Sustainable Development Goal (SDG) 9: Industry, Innovation, and Infrastructure, as the improved performance achieved through an optimal exhaust manifold design configuration is expected to promote domestic technology development.1 20 -
PublicationComplex Impedance and Modulus Analysis on Porous and Non-Porous Scaffold Composites Due to Effect of Hydroxyapatite/Starch Proportion( 2023-01-01)
;Beh C.Y. ; ;Tan X.J. ;Mohd Nasir N.F. ; ; ; ;Lee K.Y.This study aims to investigate the electric responses (complex modulus and complex impedance analysis) of hydroxyapatite/starch bone scaffold as a function of hydroxyapatite/starch proportion and the microstructural features. Hence, the non-porous and porous hydroxyapatite/starch composites were fabricated with various hydroxyapatite/starch proportions (70/30, 60/40, 50/50, 40/60, 30/70, 20/80, and 10/90 wt/wt%). Microstructural analysis of the porous hydroxyapatite/starch composites was carried out by using scanning electron microscopy. It shows that the formation of hierarchical porous microstructures with high porosity is more significant at a high starch proportion. The complex modulus and complex impedance analysis were conducted to investigate the electrical conduction mechanism of the hydroxyapatite/starch composites via dielectric spectroscopy within a frequency range from 5 MHz to 12 GHz. The electrical responses of the hydroxyapatite/starch composites are highly dependent on the frequency, material proportion, and microstructures. High starch proportion and highly porous hierarchical microstructures enhance the electrical responses of the hydroxyapatite/starch composite. The material proportion and microstructure features of the hydroxyapatite/starch composites can be indirectly reflected by the simulated electrical parameters of the equivalent electrical circuit models.4 -
PublicationLow frequency dielectric and optical behavior on physicochemical properties of hydroxyapatite/cornstarch composite( 2021-10-15)
;Beh C.Y. ; ; ; ;Eng S.K. ; ;Lee K.Y.An investigation on relationship among the physicochemical, optical and dielectric properties of the hydroxyapatite/cornstarch (HA/Cs) composites with the starch proportion of 30, 40, 50, 60, 70, 80 and 90 wt% is presented in this work. The HA/Cs composites have been characterized via FTIR, XRD, DRS and impedance analyzer. This work depicts that the strong interaction is exhibited between the hydroxyapatite nanoparticles and starch as the starch proportion increases. This increment trend results in the higher crystallinity of the HA/Cs composites. The highly crystallized HA/Cs with hydroxyapatite nucleation center presents low optical properties (diffuse reflectance and optical band gap energy). The HA/Cs composite with 80 wt% starch proportion (H2C8) show higher dielectric properties (dielectric constant, loss factor and conductivity) due to the stronger interfacial interaction and close-packed HA/Cs crystalline structure. The relationship among the physicochemical, optical and dielectric properties of the HA/Cs composite is studied in this work for potential of instrumentation design.2 1 -
PublicationRegression Analysis of the Dielectric and Morphological Properties for Porous Nanohydroxyapatite/Starch Composites: A Correlative Study( 2022-05-01)
;Beh C.Y. ; ; ;Mohd Tarmizi E.Z. ; ; ;Lee K.Y.This paper aims to investigate the dielectric properties, i.e., dielectric constant (ε′), dielectric loss factor (ε″), dielectric tangent loss (tan δ), electrical conductivity (σ), and penetration depth (Dp), of the porous nanohydroxyapatite/starch composites in the function of starch proportion, pore size, and porosity over a broad band frequency range of 5 MHz–12 GHz. The porous nanohydroxyapatite/starch composites were fabricated using different starch proportions ranging from 30 to 90 wt%. The results reveal that the dielectric properties and the microstructural features of the porous nanohydroxyapatite/starch composites can be enhanced by the increment in the starch proportion. Nevertheless, the composite with 80 wt% of starch proportion exhibit low dielectric properties (ε′, ε″, tan δ, and σ) and a high penetration depth because of its highly interconnected porous microstructures. The dielectric properties of the porous nanohydroxyapatite/starch composites are highly dependent on starch proportion, average pore size, and porosity. The regression models are developed to express the dielectric properties of the porous nanohydroxyapatite/starch composites (R2 > 0.96) in the function of starch proportion, pore size, and porosity from 1 to 11 GHz. This dielectric study can facilitate the assessment of bone scaffold design in bone tissue engineering applications.1 18 -
PublicationPhysical, thermal, and mechanical properties of highly porous polylactic acid/cellulose nanofibre scaffolds prepared by salt leaching technique( 2021-01-01)
;Radakisnin R. ; ; ; ;Al Alshahrani H.This study aimed to prepare and characterise polylactic acid (PLA) reinforced with cellulose nanofibre (CNF) from a Pennisetum purpureum-based composite scaffold and determine its structural and mechanical properties. Porous scaffolds with CNF compositions of 5‒20 wt% in the PLA matrix were developed using solvent casting and particulate leaching of its porogen at 90 wt% of loadings. Morphology studies using field emission scanning electron microscopy revealed that the scaffolds had well-interconnected pores with an average pore size range of 67‒137 μm and porosity >76%. X-ray diffraction confirmed the interconnectivity and homogeneity of the pores and the fibrous structure of the scaffolds. The compressive strength of the fabricated scaffolds varied between 2.34 and 6.66 MPa, while their compressive modulus was between 1.95 and 6.04 MPa for various CNF contents. Furthermore, water absorption and thermal degradation studies showed that the scaffold had good hydrophilicity and improved thermal stability. These findings highlight the need to modify the pore structure and mechanical performance simultaneously for tissue engineering. Thus, this study concludes that the developed PLA scaffolds reinforced with CNF from Pennisetum purpureum are potential candidates for cell attachment and extracellular matrix generation.2 -
PublicationDerivation and validation of heat transfer model for Spark-Ignition engine cylinder head( 2023-05-05)
;Hassan M.A.S.M. ; ; ; ; ; ;Ibrahim Z. ;Ishak A.A.The valve train is located in the engine cylinder head, which has various operational heat transfer mechanisms to accommodate the combustion process. Most heat transfer studies in this area have only addressed medium-to high-power vehicles at a single running speed. In this study, a model of an air-cooled underbone motorcycle valve, valve seat, and engine cylinder head was tested to determine the thermal characteristics using actual engine operating conditions at low, medium, and high engine speeds. One-dimensional thermal simulation analyses were conducted to obtain the instantaneous heat-transfer coefficients of an actual engine. The average thermal value was determined as the boundary condition in the three-dimensional thermal analysis. A three-dimensional model was prepared using the ANSYS commercial computational fluid dynamics software package. The results show that as the engine speed increases, so does the thermal load toward the component in the engine cylinder head. The strongest temperature regions were concentrated around the combustion face. The exhaust valve held most of the heat, with the valve neck recording the highest temperature. For the intake valve, the combustion face registered the majority of the heat. The heat flux intensity was gathered in the contact surface area between the valve and its seat, between the valve stem and guide, and between the stem guide and tip section. A thermal survey was used to validate the three modelling results for two separate engine datasets. The cumulative relative errors for intake and exhaust valve seats for low engine speeds were 3.73% and 0.17%, respectively. The intake and exhaust valve seats had cumulative relative errors of 4.12% and 0.70%, respectively, at intermediate speeds. This methodology provides valuable information for analysing the heat characterisation of air-cooled engines. It can also be a useful blueprint for the automotive industry and other researchers involved in thermal measurements.32 2 -
PublicationEffect of Water Absorption on Graphene Nanoplatelet and Multiwalled Carbon Nanotubes-impregnated Glass Fibre-Reinforced Epoxy Composites( 2023-07-01)
;Ahmad M.A.A. ; ; ;Sapuan S.M. ;In this study, the effect of water uptake on graphene nanoplatelets (GNP) and multiwalled carbon nanotube (MWCNT)-impregnated glass fibre-reinforced epoxy composites was examined. The composite was manufactured using a hand lay-up and vacuum bagging technique. The nanofiller was mixed with epoxy using a mechanical stirrer, high-shear mixer, and ultrasonic probe machine. In situ electromechanical testing was performed on the specimens. The study found that the weight content and type of nanofiller impact the composites' water uptake and mechanical properties. The water uptake of GNP–glass, MWCNT–glass, and GNP–MWCNT–glass hybrid composites decrease with the addition of different nanofiller contents. Adding a 1.5 GNP–MWCNT hybrid mixture increased the composite's tensile and flexural strengths to 269.3 and 294.4 MPa, respectively. The GNP–MWCNT–glass hybrid composite shows a positive synergy effect on the enhancement of water-ageing with self-sensing ability, while the GNP–glass, MWCNT–glass composites show a less positive effect on water ageing sensing behaviour. The nanofillers dispersion and fracture surface morphological observations were disclosed using a field emission scanning electron microscope. The results established that the GNP–MWCNT–glass hybrid exhibits good potential for in situ damage monitoring of composites and can support their development and application as a smart material.6 22