Now showing 1 - 10 of 16
Thumbnail Image
Publication

Effect of NaOH molar concentration on microstructure and compressive strength of Dolomite/Fly Ash-Based geopolymers

2021 , Emy Aizat Azimi , M.A.A. Mohd Salleh , Mohd. Mustafa Al Bakri Abdullah , Ikmal Hakem A. Aziz , Kamarudin Hussin , Jitrin Chaiprapa , Petrica Vizureanu , Sorachon Yoriya , Marcin Nabiałek , Jerzy J. Wyslocki

Dolomite can be used as a source of aluminosilicate to produce geopolymers; however, this approach is limited by its low reactivity. This study analyzes the viability of producing geopolymers using dolomite/fly-ash with sodium silicate and NaOH solutions (at multiple concentrations) by determining the resultant geopolymers’ compressive strengths. The dolomite/fly-ash-based geopolymers at a NaOH concentration of ~22 M resulted in an optimum compressive strength of 46.38 MPa after being cured for 28 days, and the SEM and FTIR analyses confirmed the denser surface of the geopolymer matrix. The synchrotron micro-XRF analyses confirmed that the Ca concentration exceeded that of Si and Mg, leading to the formation of calcium silicate hydrate, which strengthens the resulting geopolymers.

Thumbnail Image
Publication

Tool wear and surface evaluation in drilling fly ash geopolymer using HSS, HSS-Co, and HSS-TiN cutting tools

2021 , Mohd Fathullah Ghazli@Ghazali , Mohd. Mustafa Al Bakri Abdullah , Shayfull Zamree Abd. Rahim , Joanna Gondro , Paweł Pietrusiewicz , Sebastian Garus , Tomasz Stachowiak , Andrei Victor Sandu , Muhammad Faheem Mohd. Tahir , Mehmet Erdi Korkmaz , Mohamed Syazwan Osman

This paper reports on the potential use of geopolymer in the drilling process, with respect to tool wear and surface roughness. The objectives of this research are to analyze the tool life of three different economy-grade drill bit uncoated; high-speed steel (HSS), HSS coated with TiN (HSS-TiN), and HSS-cobalt (HSS-Co) in the drilling of geopolymer and to investigate the effect of spindle speed towards the tool life and surface roughness. It was found that, based on the range of parameters set in this experiment, the spindle speed is directly proportional to the tool wear and inversely proportional to surface roughness. It was also observed that HSS-Co produced the lowest value of surface roughness compared to HSS-TiN and uncoated HSS and therefore is the most favorable tool to be used for drilling the material. For HSS, HSS coated with TiN, and HSS-Co, only the drilling with the spindle speed of 100 rpm was able to drill 15 holes without surpassing the maximum tool wear of 0.10 mm. HSS-Co exhibits the greatest tool life by showing the lowest value of flank wear and produce a better surface finish to the sample by a low value of surface roughness value (Ra). This finding explains that geopolymer is possible to be drilled, and therefore, ranges of cutting tools and parameters suggested can be a guideline for researchers and manufacturers to drill geopolymer for further applications

Thumbnail Image
Publication

Influence of salinity of mixing water towards physical and mechanical properties of high strength concrete

2023 , Rafiza Abd Razak , Khai Yen Ng , Mohd. Mustafa Al Bakri Abdullah , Zarina Yahya , M. Nabiałek , K. Muthusamy , W.A.W. Jusoh , B. Jeż , R. Mohamed

Dramatic population and economic growth result in increasing demand for concrete infrastructure, which leads to an increment of freshwater demand and a reduction of freshwater resources. However, freshwater is a finite resource, which means that freshwater will be used up someday in the future when freshwater demand keeps increasing while freshwater resources are limited. Therefore, replacing freshwater with seawater in concrete blending seems potentially beneficial for maintaining the freshwater resources as well as advantageous alternatives to the construction work near the sea. There have been few experimental research on the effect of blending water salt content on the mechanical and physical characteristics of concrete, particularly high-strength concrete. Therefore, a research study on the influence of salt concentration of blending water on the physical and mechanical properties of high-strength concrete is necessary. This study covered the blending water salinity, which varied from 17.5 g/L to 52.5 g/L and was determined on the physical and mechanical properties, including workability, density, compressive strength, and flexural strength. The test results indicate that the use of sea salt in blending water had a slight negative influence on both the workability and the density of high strength concrete. It also indicates that the use of sea salt in blending water had a positive influence on both the compressive strength and the flexural strength of high-strength concrete in an earlystage.

Thumbnail Image
Publication

Hierarchical carbon fiber-carbon nanotubes by using electrospray deposition method with preserved tensile properties

2022 , Muhammad Razlan Zakaria , Hazizan Md Akil , Mohd Firdaus Omar , Mohd. Mustafa Al Bakri Abdullah , Shayfull Zamree Abd. Rahim , M. Nabiałek , J.J. Wysłocki

In this study, the electrospray deposition (ESD) method was used to deposit carbon nanotubes (CNT) onto the surfaces of carbon fibers (CF) in order to produce hybrid carbon fiber-carbon nanotubes (CF-CNT) which is rarely reported in the past. Extreme high-resolution field emission scanning electron microscopy (XHR-FESEM), high-resolution transmission electron microscopy (HRTEM) and x-ray photoelectron spectroscopy (XPS) were used to analyse the hybrid carbon fiber-carbon nanotube (CF-CNT). The results demonstrated that CNT was successfully and homogenously distributed on the CF surface. Hybrid CF-CNT was then prepared and compared with CF without CNT deposition in terms of their tensile properties. Statistically, the tensile strength and the tensile modulus of the hybrid CF-CNT were increased by up to 3% and 25%, respectively, as compared to the CF without CNT deposition. The results indicated that the ESD method did not cause any reduction of tensile properties of hybrid CF-CNT. Based on this finding, it can be prominently identified some new and significant information of interest to researchers and industrialists working on CF based products

Thumbnail Image
Publication

Assessment of the suitability of ceramic waste in geopolymer composites: an appraisal

2021 , Ismail Luhar , Salmabanu Luhar , Mohd. Mustafa Al Bakri Abdullah , Marcin Nabiałek , Andrei Victor Sandu , Janusz Szmidla , Anna Jurczyńska , Rafiza Abdul Razak , Ikmal Hakem A Aziz , Noorina Hidayu Jamil , Laila Mardiah Deraman

Currently, novel inorganic alumino-silicate materials, known as geopolymer composites, have emerged swiftly as an ecobenevolent alternative to contemporary ordinary Portland cement (OPC) building materials since they display superior physical and chemical attributes with a diverse range of possible potential applications. The said innovative geopolymer technology necessitates less energy and low carbon footprints as compared to OPC-based materials because of the incorporation of wastes and/or industrial byproducts as binders replacing OPC. The key constituents of ceramic are silica and alumina and, hence, have the potential to be employed as an aggregate to manufacture ceramic geopolymer concrete. The present manuscript presents a review of the performance of geopolymer composites incorporated with ceramic waste, concerning workability, strength, durability, and elevated resistance evaluation.

Thumbnail Image
Publication

Properties of stone mastic asphalt incorporating nano titanium as binder's modifier

2022 , Nur Syafiqah Shamimi Mohd Zali , Khairil Azman Masri , Ramadhansyah Putra Jaya , Mohd. Mustafa Al Bakri Abdullah , Muzamir Hasan , Mohd Rosli Mohd Hasan , Bartłomiej Jeż , Marcin Nabiałek , Marek Sroka , Paweł Pietrusiewicz

Stone mastic asphalt is a gap-graded mix and is usually related to its high bitumen content and its skeleton-like constitution. Although famous for its durability, high resistance to fatigue and rutting, issues such as bleeding and premature aging do occur in the mix since it has a high bitumen content and voids due to its gap-graded structure. In order to encounter these problems from affecting the mix, some instances such as adding additives, rejuvenators and stabilizers into the mixture has been implemented. Nowadays, nano materials are being used in the asphalt mixtures and nano titanium is being introduced as a modifier to the asphalt binder in order to improve the mechanical properties of the stone mastic asphalt mix. The related tests done in order to access the improvement are resilient modulus, dynamic creep, moisture susceptibility and binder drain down. The content of nano titanium used in this research are 1%, 2%, 3%, 4% and 5%. This study is done to assess the mechanical performance of stone mastic asphalt with nano titanium modified binder.

Thumbnail Image
Publication

The effect of thermal annealing on the microstructure and mechanical properties of Sn-0.7Cu-xZn solder joint

2021 , Mohd Izrul Izwan Ramli , Mohd Arif Anuar Mohd Salleh , Rita Mohd Said , Mohd. Mustafa Al Bakri Abdullah , Dewi Suriyani Che Halin , Norainiza Saud , Marcin Nabiałek

The microstructural properties of a Pb-free solder joint significantly affect its mechanical behaviours. This paper details a systematic study of the effect of the annealing process on the microstructure and shear strength of a Zn-added Sn-0.7Cu solder joint. The results indicated that the IMC layer’s thickness at the solder/Cu interface increases with annealing time. The interfacial IMC layer of the Sn-0.7Cu solder joint gradually thickened with increasing annealing time and annealing temperature, while the interfacial IMC layer’s morphology changed from scallop-type to layer-type after the annealing process. However, the addition of 1.0 wt.% and 1.5 wt.% Zn in the Sn-0.7Cu effectively altered the interfacial IMC phase to Cu-Zn and suppressed the growth of Cu3Sn during the annealing process. The single-lap shear tests results confirmed that the addition of Zn decreased the shear strength of Sn-0.7Cu. The interfacial IMC of the Cu6Sn5 phase in Sn-0.7Cu changed to Cu-Zn due to the addition of Zn. The shear fractures in the annealed solder joint were ductile within the bulk solder instead of the interfacial IMC layer. Increased annealing time resulted in the increased presence of the Cu-Zn phase, which decreased the hardness and shear strength of the Sn-0.7Cu solder joint.

Thumbnail Image
Publication

Role of sintering temperature in production of nepheline Ceramics-Based geopolymer with addition of ultra-high molecular weight polyethylene

2021 , Romisuhani Ahmad , Fakhryna Hannanee Ahmad Zaidi , Mohd. Mustafa Al Bakri Abdullah , Wan Mastura Wan Ibrahim , Jitrin Chaiprapa , Kamarudin Hussin , Jerzy J. Wysłocki , Katarzyna Błoch , Marcin Nabiałek

The primary motivation of developing ceramic materials using geopolymer method is to minimize the reliance on high sintering temperatures. The ultra-high molecular weight polyethylene (UHMWPE) was added as binder and reinforces the nepheline ceramics based geopolymer. The samples were sintered at 900 °C, 1000 °C, 1100 °C, and 1200 °C to elucidate the influence of sintering on the physical and microstructural properties. The results indicated that a maximum flexural strength of 92 MPa is attainable once the samples are used to be sintered at 1200 °C. It was also determined that the density, porosity, volumetric shrinkage, and water absorption of the samples also affected by the sintering due to the change of microstructure and crystallinity. The IR spectra reveal that the band at around 1400 cm−1 becomes weak, indicating that sodium carbonate decomposed and began to react with the silica and alumina released from gels to form nepheline phases. The sintering process influence in the development of the final microstructure thus improving the properties of the ceramic materials.

Thumbnail Image
Publication

Crumb rubber geopolymer mortar at elevated temperature exposure

2022 , Ahmad Azrem Azmi , Mohd. Mustafa Al Bakri Abdullah , Che Mohd Ruzaidi Ghazali , Romisuhani Ahmad , Ramadhansyah Putra Jaya , Shayfull Zamree Abd. Rahim , Mohammad A. Almadani , Wysłocki, Jerzy J. , Agata Śliwa , Andre Victor Sandu

Low calcium fly ash is used as the main material in the mixture and the crumb rubber was used in replacing fine aggregates in geopolymer mortar. Sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) which were high alkaline solution were incorporated as the alkaline solution. The fly ash reacted with the alkaline solution forming alumino-silicate gel that binds the aggregate to produce a geopolymer mortar. The loading of crumb rubber in the fly ash based geopolymer mortar was set at 0%

Thumbnail Image
Publication

The effect of particle size on the mechanical properties of Alkali Activated Steel Slag Mortar

2022 , Doh Shu Ing , Ho Chia Min , Xiaofeng Li , Ramadhansyah Putra Jaya , Mohd. Mustafa Al Bakri Abdullah , Siew Choo Chin , Nur Liza Rahim , Marcin Nabiałek

With the rapid development of industry, abundant industrial waste has resulted in escalating environmental issue. Steel slag is the by-product of steel-making and can be used as cementitious materials in construction. However, the low activity of steel slag limits its utilization. Much investigation has been conducted on steel slag, while only a fraction of the investigation focuses on the effect of steel slag particle size on the properties of mortar. The aim of this study is to investigate the effect of steel slag particle size as cement replacement on properties of steel slag mortar activated by sodium sulphate (Na 2 SO 4). In this study, two types of steel slag, classified as fine steel slag (FSS) with particle sizes of 0.075mm and coarse steel slag (CSS) with particle sizes of 0.150 mm, were used for making alkali activated steel slag (AASS) mortar. Flow table test, compressive strength test, flexural strength test and UPV test were carried out by designing and producing AASS mortar cubes of (50 × 50 × 50) mm at 0, 10%, 20% and 30% replacement ratio and at 0.85% addition of Na 2 SO 4. The results show that the AASS mortar with FSS possess a relatively good strength in AASS mortar. AASS mortar with FSS which is relatively finer shows a higher compressive strength than CSS up to 38.0% with replacement 52 DOH SHU ING et al. ratio from 10% to 30%. This study provided the further investigation on the combined influence of replacement ratio and particle size of SS in the properties of fresh and hardened AASS.