Showing papers by "Faizal Mustapha published in 2021"

Review of current research progress related to magnetorheological elastomer material

Abstract: Magnetorheological (MR) material started to gain exposure when researchers explore the potential of magnetic field-responsive material based on fluid (MRF), foam (MR foam), elastomer (MRE), and gel (MRG). Magnetorheological elastomer (MRE) is a smart material in which its physical properties can be changed rapidly and reversibly under varying magnetic field strength. Due to the potential commercialization of MRE-based devices, the fundamental factors that affect the rheological and mechanical properties of MRE need to be identified and documented properly. Various factors such as ferromagnetic particles' condition, elastomer matrix's condition, strain amplitude, exciting frequency, temperature, and many more have been reviewed and presented with supporting figures highlighting the MRE's current findings. A collection of MRE-based devices is also presented to summarize the applications explored by current researchers. A few challenges in the MRE research require immediate attention. It includes designing an innovative MRE fabrication equipment incorporating an electromagnet to permit anisotropic particle configuration during crosslinking. Moreover, an optimum thickness of MRE needs to be studied in every MRE-based device design to ensure that the magnetic field is optimized thoroughly. Therefore, more studies ought to be done to improve the MRE that can enable the commercialization of MRE in various applications.

Rheological and Morphological Properties of Oil Palm Fiber-Reinforced Thermoplastic Composites for Fused Deposition Modeling (FDM).

Abstract: Fused deposition modelling (FDM) is a filament-based rapid prototyping technology that allows new composite materials to be introduced into the FDM process as long as they can be manufactured in feedstock filament form. The purpose of this research was to analyze the rheological behavior of oil palm fiber-reinforced acrylonitrile butadiene styrene (ABS) composites when used as a feedstock material, as well as to determine the best processing conditions for FDM. The composite’s shear thinning behavior was observed, and scanning electron microscopy was used to reveal its composition. The morphological result found that there was a good fiber/matrix adhesion with a 3 wt% fiber loading, as no fiber pullouts or gaps developed between the oil palm fiber and ABS. However, some pores and fiber pullouts were found with a 5 and 7 wt% fiber loading. Next, the rheological results showed that the increment of fiber content (wt%) increased the viscosity. This discovery can definitely be used in the extrusion process for making wire filament for FDM. The shear thinning effect was increased by adding 3, 5, or 7 wt% of oil palm fiber. The non-Newtonian index (n) of the composites increased as the number of shear rates increased, indicating that the fiber loading had a significant impact on the rheological behavior. As the fiber loading increased, the viscosity and shear stress values increased as well. As a result, oil fiber reinforced polymer composites can be used as a feedstock filament for FDM.

Study and Use of Rice Husk Ash as a Source of Aluminosilicate in Refractory Coating.

Abstract: The utilisation of rice husk ash (RHA) as an aluminosilicate source in fire-resistant coating could reduce environmental pollution and can turn agricultural waste into industrial wealth. The overall objective of this research is to develop a rice-husk-ash-based geopolymer binder (GB) fire-retardant additive (FR) for alkyd paint. Response surface methodology (RSM) was used to design the experiments work, on the ratio of RHA-based GB to alkyd paint. The microstructure behaviour and material characterisation of the coating samples were studied through SEM analysis. The optimal RHA-based GB FR additive was formulated at 50% wt. FR and 82.628% wt. paint. This formulation showed the result of 270 s to reach 200 °C and 276 °C temperature at equilibrium for thermal properties. Furthermore, it was observed that the increased contents of RHA showed an increment in terms of the total and open porosities and rough surfaces, in which the number of pores on the coating surface plays an important role in the formation of the intumescent char layer. By developing the optimum RHA-based GB to paint formulation, the coating may potentially improve building fire safety through passive fire protection.

Testing of Silicon Rubber/Montmorillonite Nanocomposite for Mechanical and Tribological Performance.

Abstract: Nanocomposite made by blending nano-montmorillonite (MMT) and Silicon Rubber (SR) for mechanical and tribological performance is explored in this work. Different configurations of MMT/SR nanocomposite, with 0, 0.5, 2 and 5 wt % of MMT are manufactured by two roll mixing methods. Noticeable improvement in the mechanical and tribological performance is observed, which is also justified by a morphological study of fractured and wear surfaces through SEM. Two percent of MMT loading is found to be the optimum content that shows excellent performance compared to other compositions. The performance improvement can be linked to the good interfacial interaction between the MMT and SR. Statistical modeling through ANOVA is carried out for tribological performance, which reveals the influence of load on the coefficient of friction (COF) and the influence of sliding distance on the wear rate.

Rice-Husk-Ash-Based Geopolymer Coating: Fire-Retardant, Optimize Composition, Microstructural, Thermal and Element Characteristics Analysis.

Abstract: Geopolymer using aluminosilicate sources, such as fly ash, metakaolin and blast furnace slag, possessed excellent fire-retardant properties. However, research on the fire-retardant properties and thermal properties of geopolymer coating using rice husk ash (RHA) is rather limited. Additionally, the approach adopted in past studies on geopolymer coating was the less efficient one-factor-at-a-time (OFAT). A better approach is to employ statistical analysis and a regression coefficient model (mathematical model) in understanding the optimum value and significant effect of factors on fire-retardant and thermal properties of the geopolymer coating. This study aims to elucidate the significance of rice husk ash/activated alkaline solution (RHA/AA) ratio and NaOH concentration on the fire-retardant and thermal properties of RHA-based geopolymer coating, determine the optimum composition and examine the microstructure and element characteristics of the RHA-based geopolymer coating. The factors chosen for this study were the RHA/AA ratio and the NaOH concentration. Rice husk was burnt at a temperature of approximately 600 °C for 24 h to produce RHA. The response surface methodology (RSM) was used to design the experiments and conduct the analyses. Fire-retardant tests and thermal and element characteristics analysis (TGA, XRD, DSC and CTE) were conducted. The microstructure of the geopolymer samples was investigated by using a scanning electron microscope (SEM). The results showed that the RHA/AA ratio had the strongest effect on the temperature at equilibrium (TAE) and time taken to reach 300 °C (TT300). For the optimization process using RSM, the optimum value for TAE and TT300 could be attained when the RHA/AA ratio and NaOH concentration were 0.30 and 6 M, respectively. SEM micrographs of good fire-resistance properties showed a glassy appearance, and the surface coating changed into a dense geopolymer gel covered with thin needles when fired. It showed high insulating capacity and low thermal expansion; it had minimal mismatch with the substrate, and the coating had no evidence of crack formation and had a low dehydration rate. Using RHA as an aluminosilicate source has proven to be a promising alternative. Using it as coating materials can potentially improve fire safety in the construction of residential and commercial buildings.

Damage Identification on Impact and Lightning Damage of Flax Composite Laminates (Linum usitatissimum) Using Long-Pulse Thermography of a Low-Resolution Infrared Camera

Abstract: The demand for composite fiber material is significantly high due to its excellent mechanical properties and has been used in various industries. Recently, with the increasing awareness on the environmental issues, researchers are now focusing more on eco-friendly and green materials. Bio composite offers a good balance of strength and stiffness ratio, bending and membrane mechanical properties, balanced thermal distortion stability, reduced weight and cost, improved fatigue resistance, reduced notch sensitivity and comparatively having better performance compared to synthetic composite. Yet, due to their complex anisotropy of the composite material, the inspection and detection of inner defects become a challenge. Long pulse thermography is one of non-destructive evaluation to detect defect of composite materials However, very limited research into the usage of low-resolution infrared camera to perform defect damage inspection on Flax composite laminates. In this paper, an experimental set-up of Long Pulse thermography system using a low-resolution infrared camera of flax bio-composite on impact and lightning damage defects. The result highlight that with control parameters, a low-resolution infrared camera has the capability to capture lightning and impact defect of flax bio-composite defect using long pulse thermography system. An Image processing method is then applied to the defect to improve the quality of defect detection and reduce background noise.

Preliminary Design of a Low-Resolution Thermography Camera System for Subsurface Defect Detection of a Thin Composite Plate; A Case Study for Composite Electric Bus Structure

Abstract: The use of electric vehicle especially electric bus in on the rise. Unfortunately, it still has a downside which is not having enough distance compared to the conventional bus which uses diesel as its energy source. One of the reasons that affect the distance the electric bus can travel is the weight of the bus. The lighter the bus, the longer it can travel. Because of that, a new way of building the chassis and bus body structure that uses the composite material to replace not just heavy but also rusty prone metallic material has been developed. Now that the weight has improved, it creates another problem where the current method of inspecting the quality of the product during manufacturing is not just error-prone, but also take a longer time than it is allocated. The available tool in the market is expensive and a lot of investment is needed to make it work with a large structure such as the bus that a small company could not afford. Due to that, this project is going to address the need by designing and developing a thermal imaging tool for composite damage detection. The design process is done by using a model-based systems engineering method to identify the needs of the user and develop the functional requirement it needs based on that. Then, the structure of the tool is allocated to the functional requirement and eventually, the hardware needed for it to become a complete product is identified. Once the hardware has been identified, it now can be integrated and several conceptual housing designs are developed where the final selection of the design is selected by using the Pugh evaluation matrix method. The integrated hardware is then put to test to ensure the tool works as intended. Based on the experiment conducted, the tool can detect a sub-surface damaged-induced specimen up to 2 mm depth. More than that, a longer time is needed which is not productive. In conclusion, although the developed tool meets all its objectives, there is still room for improvement to make it work efficiently in the field.