Marina Marzuki
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Preferred name
Marina Marzuki
Official Name
Marina, Marzuki
Alternative Name
Marzuki, Marina
Marina, M
Main Affiliation
Scopus Author ID
46261384500
Researcher ID
FOF-4552-2022

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  • Publication
    Fabrication and characterization of microwave sintered PM Fe-Cr-Y₂O₃ composite
    ( 2013)
    Marina Marzuki
    This research is focused on assessing the feasibility of the innovative microwave sintering technology for fabricating iron – chromium composites via powder metallurgy route. The microwave sintered composites were compared with their conventionally sintered counterparts in terms of physical and mechanical properties (micro Vickers hardness and compressive strength). Microwave sintering is proved feasible to consolidate the composite. The result also revealed that the microwave sintered iron chromium composites possess improved density, micro hardness and compressive strength compared to the conventionally sintered composites. Process evaluation also revealed that microwave assisted sintering can lead to reduction of 70% of sintering time when compared to conventional sintering. Another aims of this research is to study the effect adding varying weight fraction of yttria reinforcement to the iron chromium composites. For this purpose iron-chromium composites is reinforced with 5, 10, 15 and 20 wt.% of the ceramic particulates. From the study it is observed that the mechanical properties of microwave sintered iron – chromium composites improved with the addition of 5 wt.% ceramic content. For the conventional sintered composites, highest micro hardness and compressive strength were obtained from the 10 wt.% reinforced composites.The highest hardness value is given by microwave sintered composite. Other physical properties such as density was decreased as the reinforcement content increased. This is due to the increasing presence of porosity in the composites. However, microwave sintered composites exhibit better density relative to theoretical density and densification behaviour.
  • Publication
    High specific heterocontacts of p-CuO/n-ZnO thin film composites for enhanced sunlight absorption
    ( 2020-12-18)
    Syazwani A.S.
    ;
    Marina Marzuki
    ;
    Wan Abdul Rahman Assyahid Wan Ibrahim
    ;
    Mohd Zamzuri Mohammad Zain
    ;
    Hadi H.
    ;
    Syahmi R.M.A.
    This study is focused on investigating the heterocontacts development between p-CuO and n-ZnO semiconductor composite for enhancing its sunlight absorption. CuO and ZnO are chosen as precursors due to their many potentials. High absorption of sunlight is one of the most important criteria in photovoltaic (PV) device. However poor crystal structure and low contact surface between the p and n semiconductors limits the light intake and is due to several factors. To carry out intensive study on the mechanism of the heterocontact growth, CuO:ZnO thin film is synthesized by mechanical alloying process using high energy ball mill (HEBM) followed by sol gel technique. Three parameters were studied; sol-gel's surfactant to solvent ratio, annealing temperature and annealing duration. The homogeneity and compounds' distribution of the composite is analysed by EDS analysis and structural characterization is done with XRD analysis. The UV-VIS analysis is done to determine the light absorbance and the bandgap of the composite. The initial mechanical centrifugation HEBM has aided the process for homogenizing the composite and boost the heterointerface between the semiconductors by mechanochemical effects such as phase transformations and solid-state reactions. EDS analysis reported that 500 C annealed specimen giving the lowest percentage of ratio gap than others temperature and the heterocontact surface between molecules of material also increased. Uv-Vis analysis also agrees with EDS, showing the specimen having highest absorbance spectra. However, bandgap narrowing occurred in the specimen, as resulted by the coexistence of transitional metal Cu in the composite system. XRD analysis shows a near single oriented crystal growth which promotes clean growth of crystal structure and hypothetically reduce the presence of unwanted voids and large boundaries.
  • Publication
    Optimization of compacting process for porous Ti-6Al-7Nb alloys with magnesium as a space holder by using
    ( 2022-10)
    M N Fazlen
    ;
    R. N. Ahmad
    ;
    N I N Suhaimi
    ;
    Muhamad Saifuldin Abdul Manan
    ;
    Marina Marzuki
    The optimization of compacting process for porous titanium niobium (Ti-6Al-7Nb) alloys with magnesium as a space holder prepared by powder metallurgy process was studied to analyze the significant porosity required in biomedical industry especially in bone tissue engineering. This approach helps to replace the damaged bones and solve the problem occurs during the implantation for artificial joints which is important that the implant material's stiffness is as similar to the joint bone as possible. The aim was to determine the significant factors affecting the physical and mechanical properties performance of porous Ti-6Al-7Nb alloys such as density and strength. Firstly, the Ti-6Al-7Nb were mixed with magnesium with weight percentage of 20%, 30%, and 40% as a spacer material for 30 minutes using Fritsch Pulverisette Mill mixer machine. Then, for compacting process, pressure in the range of 400MPa, 500 MPa and 600MPa were applied to the powder mixtures in a 13 mm cylindrical die by using manual hydraulic hand press machine. Compacting parameters have been optimized using Taguchi method of L-9 (34) orthogonal array. From the ANOVA results, density shows that holding time played as the most effected significant factor with 37.77% and compression was 59.47% for composition sample. The study demonstrated that many factors has been successfully optimized simultaneously, and a lot of quantitative information can be extracted from fewer experimental trials by using Taguchi method in compacting process.
  • Publication
    Doping content dependencies on the structure modification and bandgap broadening of Al induced sol-gel derived ZnO nanostructures
    ( 2021-10)
    Marina Marzuki
    ;
    Mohd Zamzuri Mohammad Zain
    ;
    Wan Abd Rahman Assyahid Wan Ibrahim
    ;
    Nooraizedfiza Zainon
    ;
    Rozie Nani Ahmad
    This paper reports the Al doping content dependence on structure modification and band gap wid-ening of sol-gel synthesised Al-doped ZnO thin films. The precursor, solvent and stabiliser used to prepare ZnO solution were Zinc Acetate Dihydrate, 2-propanol and ethanolamine, respectively. Mo-larity fractions of 0, 4, 6 and 8% of Al (NO3)2 as dopant source was incorporated into ZnO host system and prepared by individual buffer solutions. The prepared sols were subsequently deposited onto ITO glass substrates, and the resultant thin films were characterised. XRD patterns exhibit the polycrys-talline nature of pure and doped ZnO films, with preferred orientations correspond to (1 0 0), (0 0 2) and (1 0 1) planes. Lattice shrinking is indicated by the decrease lattice constant c due to axial com-pression. Peaks shifting towards higher angle are observed implying a structural modification over doped thin films that affects the optical properties, which agrees with the lattice shrinking. The ab-sorption edge has an obvious blueshift to the shorter wavelength with increased dopant content. The thin films’ energy bands were procured by Tauc’s linear extrapolation and was found to be broaden-ing from 3.32 eV to 3.34 eV in 6% Al-doped ZnO. There exists a significant correlation between the applied doping level and the extend of variation of structural properties and ultimately, lattice im-perfection. Doping of smaller-atom-sized Al into ZnO concedes with the Burstein-Moss principles. 6% Al doping imposes the highest peak shift and ultimately has the highest impact on lattice parameter and energy band.
  • Publication
    Image Processing Approach for Detection and Quantification of Corrosion Behaviour of AZ91D Magnesium Alloy
    ( 2022-01-01)
    Zuraila Iberahim
    ;
    Mohd Zamzuri Mohammad Zain
    ;
    Abdul Halim Ismail
    ;
    Alias J.
    ;
    Muhammad Aiman Ahmad Fozi
    ;
    Nooraizedfiza Zainon
    ;
    Marina Marzuki
    The AZ91D magnesium alloy is known for its high strength-to-weight ratio, excellent machinability and good castability making it an ideal material to be used in automotive components fabrication. But due to its weak corrosion resistance towards the environment, identifying and quantifying AZ91D magnesium alloy corrosion behaviour before any manufacturing processes can be a huge impact and may provide useful information to the manufacturers. The limitation of conventional corrosion detection and quantification methods also justify the further needs of image processing approach in this study. This paper study the feasibility of an image processing approach using the automatic thresholding method and various manual thresholding level in order to identify the corrosion attack on the AZ91D magnesium alloy. This method converts the original colour image to grayscale image and then convert it to binary image. Then through image processing approach, the image will be segmented to non-corroded and corroded area and labelled as 0 (black) and 1 (white) and make it easier to analyze. The white dots (1) distribution was then presented in percentage to shows that the pitting corrosion on the surface can be identified better by using the Otsu’s method of automatic thresholding. The resulting image of various thresholding shows which thresholding values successfully portray similarity of the original corrosion image. Thus, this increases the reliability of AZ91D magnesium alloy corrosion detection and quantification via image processing approach.
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