Now showing 1 - 4 of 4
  • Publication
    Void distributions in Sn-3.0Ag-0.5Cu (SAC305) composite lead free solder subjected to thermal ageing using acoustic micro imaging technique
    The formations of the voids in SAC305 lead free solder and SAC305 with additions of kaolin geopolymer ceramics were studied. The composite solders were fabricated by using powder metallurgy with microwave sintering method. The samples were sandwiched between two copper substrates and reflowed in a reflow oven and aged at 125°C for 0 and 7 days. The acoustic micro imaging was used to analyse the distributions of voids in the solder joints of SAC305 and SAC305 with additions of kaolin geopolymer ceramics. Results shows that, rhe void in SAC305 are larger in size and numbers as compared to SAC305 with additions of kaolin geopolymer ceramics for both reflowed and aged conditions.
  • Publication
    Strength development and elemental distribution of Dolomite/Fly Ash geopolymer composite under elevated temperature
    ( 2020)
    Emy Aizat Azimi
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    ;
    Petrica Vizureanu
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    ;
    Jitrin Chaiprapa
    ;
    Sorachon Yoriya
    ;
    Andrei Victor Sandu
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    ;
    Ikmal Hakem Aziz
    A geopolymer has been reckoned as a rising technology with huge potential for application across the globe. Dolomite refers to a material that can be used raw in producing geopolymers. Nevertheless, dolomite has slow strength development due to its low reactivity as a geopolymer. In this study, dolomite/fly ash (DFA) geopolymer composites were produced with dolomite, fly ash, sodium hydroxide, and liquid sodium silicate. A compression test was carried out on DFA geopolymers to determine the strength of the composite, while a synchrotron Micro-Xray Fluorescence (Micro-XRF) test was performed to assess the elemental distribution in the geopolymer composite. The temperature applied in this study generated promising properties of DFA geopolymers, especially in strength, which displayed increments up to 74.48 MPa as the optimum value. Heat seemed to enhance the strength development of DFA geopolymer composites. The elemental distribution analysis revealed exceptional outcomes for the composites, particularly exposure up to 400 °C, which signified the homogeneity of the DFA composites. Temperatures exceeding 400 °C accelerated the strength development, thus increasing the strength of the DFA composites. This appears to be unique because the strength of ordinary Portland Cement (OPC) and other geopolymers composed of other raw materials is typically either maintained or decreases due to increased heat.
      4  14
  • Publication
    Properties of a new insulation material glass bubble in geopolymer concrete
    ( 2021)
    Noor Fifinatasha Shahedan
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    ; ;
    Andri Kusbiantoro
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    Sam Tammas-Williams
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    Petrică Vizureanu
    ;
    Jerzy J. Wysłocki
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    Ikmal Hakem Aziz
    ;
    Katarzyna Błoch
    ;
    Marcin Nabiałek
    This paper details analytical research results into a novel geopolymer concrete embedded with glass bubble as its thermal insulating material, fly ash as its precursor material, and a combination of sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) as its alkaline activator to form a geopolymer system. The workability, density, compressive strength (per curing days), and water absorption of the sample loaded at 10% glass bubble (loading level determined to satisfy the minimum strength requirement of a load-bearing structure) were 70 mm, 2165 kg/m3, 52.58 MPa (28 days), 54.92 MPa (60 days), and 65.25 MPa (90 days), and 3.73 %, respectively. The thermal conductivity for geopolymer concrete decreased from 1.47 to 1.19 W/mK, while the thermal diffusivity decreased from 1.88 to 1.02 mm2/s due to increased specific heat from 0.96 to 1.73 MJ/m3K. The improved physicomechanical and thermal (insulating) properties resulting from embedding a glass bubble as an insulating material into geopolymer concrete resulted in a viable composite for use in the construction industry.
      4  11
  • Publication
    Effect of Iron Oxide (Fe2O3) on the Properties of Fly Ash Based Geopolymer
    (IOP Publishing Ltd., 2020)
    W W A Zailani
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    M F Arshad
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    D D Burduhos-Nergis
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    Geopolymer is an attractive construction binder owing to its ability to improve the properties of the concrete and preserves the environment from the high CO2 emission. Geopolymer technology will convert the potential hazardous industrial waste such as fly ash into valuable construction materials. However, there is a need of studying the properties of iron-based geopolymer in order to enhance the fundamental and knowledge of the geopolymer research also development in this study area. Fly ash which contains a significant amount of iron oxide (Fe2O3) was used as a precursor and tested at different curing duration (1, 3, 7, 14 and 28 days). Crystallization of iron oxide (Fe2O3) contained in the fly ash under geopolymerization process will be able to turn waste fly ash into a strong concrete materials, simultaneously creating a waste-to-wealth economy. Furthermore, the formation of fayalite detected from the microstructure characterization is mainly contribute to the strength development of the fly ash after 28 days curing.
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