Master Theses http://hdl.handle.net/123456789/1408 2026-04-09T13:07:46Z 2026-04-09T13:07:46Z NUR AHZA BINTI CHE NASIR, UniKL MIDI http://hdl.handle.net/123456789/33046 2025-09-03T01:27:42Z 2025-09-03T00:00:00Z

Title: MECHANICAL PROPERTIES AND CORROSION RESISTANCE PERFORMANCE OF EPOXY NANOCOMPOSITES AS ORGANIC COATING MATERIALS FOR METAL COATING APPLICATION Authors: NUR AHZA BINTI CHE NASIR, UniKL MIDI Abstract: Corrosion has been recognised as a cause of deterioration, failure, catastrophic accidents, and hazards in industrial and residential systems for more than 150 years, resulting in economic expenditures and societal impacts. The NACE estimates global corrosion expenses at $2,505 billion, or 3.4% of GDP. Malaysia's annual corrosion cost increased by 50.4% from $6.7 billion in 2009 to $312.4 billion in 2013. Anticorrosive properties of organic coatings, particularly epoxy coatings, have lately been studied. However, epoxy resin is brittle, has low corrosion protection, and has poor resistance to crack propagation. Hence, modifying the matrix with nanofillers is a critical approach for high-efficiency mechanical properties and corrosion protection of epoxy nanocomposites, considering well-dispersed nanofillers in the matrix. Comparison research has been conducted to examine the mechanical properties and corrosion resistance between four different nanofillers MXenes, GNPs, CNTs, and HNTs at low loading concentrations (0.1 wt.%). A solution-casting dispersion method was developed. The impact of nanofillers on mechanical properties was studied through tensile, microhardness and thermomechanical tests, while the corrosion resistance was examined by OCP and Tafel analysis. Then, the dispersion mechanism of nanofillers was evaluated by SEM and UV-Vis Spectrophotometer analysis. The improved tensile properties and microhardness were observed in all types of nanofiller/epoxy; HNTs and MXenes led to the highest improvement in tensile properties and microhardness, respectively, compared to neat epoxy. CNTs and GNPs exhibited remarkable improvement in storage modulus and Tg value, respectively. The OCP and Tafel analysis results revealed that the coatings reinforced by MXenes provided the most excellent protective performance with an inhibitory efficiency value of up to 99.999%. Besides, this work opens that HNTs exhibited better mechanical performance but poorer corrosion resistance ability due to their hydrophilic nature. The SEM analysis indicated that the morphological surfaces aligned with the tensile test result. The UV Vis spectrophotometer analysis revealed that solvent addition affects the dispersion interaction, further influencing the composite properties. The findings concluded that the inclusion of nanofillers with large aspect ratios improved mechanical and barrier properties. In contrast, agglomeration had the opposite effect, suggesting that if nanofiller homogeneity could be improved, further improvement properties may be expected. Overall, this study came to the conclusion that the improvement of nanocomposite properties is influenced by the geometry and dispersion rate of nanofillers.

2025-09-03T00:00:00Z MUHAMMAD AFZAL BIN AHMAD, UniKL MIDI http://hdl.handle.net/123456789/33045 2025-09-03T01:22:01Z 2025-09-03T00:00:00Z

Title: NUMERICAL EVALUATION OF HOT STAMPED BLANK B-PILLARS Authors: MUHAMMAD AFZAL BIN AHMAD, UniKL MIDI Abstract: The recent advances in sheet metal forming simulation technology have allowed engineers to predict the sheet metal stamped part performance prior to mass pro-duction by finite element method. However, the accuracy of such simulation meth-od is dependent on many factors such as right material model and its boundary con-ditions. This thesis describes the application of this method in the evaluation of an automotive hot stamped structural part call B-pillar and its variants. The first case study involved the optimization of spot-weld points and locations on a Patchwork blank B-pillar (PWB) made up of two blank materials of different thicknesses. The spot weld was modeled as a rigid link between the parent blank and the additional blank. Throughout the forming simulation, maximum stress and formability of the part were monitored. The same procedure was repeated by increasing the number of spot-weld points and locations. An optimum number of the spot-weld was then de-termined by the onset of wrinkle disappearance. Performance of the optimized spot-weld part was validated by the actual part. The results show the optimum number of spot weld points as predicted by the simulation is between 35-40 whereas the actual part contains 40 spot-weld points. The second case study was to evaluate the crash worthiness performance of different designs of hot formed B-pillars. In this study, in addition to PWB, three other hot formed B-Pillar designs namely Monolithic blank (MB), Tailor welded blank (TWB) and Tailor Rolled Blank (TRW) were evaluated by numerical simulation in accordance with the Insurance Institute for Highway Safety (IIHS) side impact test protocol.. For each design, maximum displacement or intrusion and energy absorption were measured. The results of intrusion tests for all blank models MB, PWB, TWB and TRB recorded displacement of 14.14cm, 14.80cm, 14.87cm and 14.98cm, respectively. These are considered as within the SAFE ZONE as specified by IHSS. However, in terms of energy absorption, the PWB is seemed to be the best performer followed by MB, TRB and TWB. More importantly, the FEM model developed in this research is quite reliable in determining the optimum number of spot weld points.

2025-09-03T00:00:00Z MOHD NOR HAZWAN BIN HADZIR, UniKL MIDI http://hdl.handle.net/123456789/33044 2025-09-03T01:18:37Z 2025-09-03T00:00:00Z

Title: DEVELOPMENT OF MAGNETORHEOLOGICAL ELASTOMER LINEAR ACTUATOR Authors: MOHD NOR HAZWAN BIN HADZIR, UniKL MIDI Abstract: Nowadays, the piezoelectric actuator is commonly used in micro-scale precision systems. However, the use of piezoelectric material is limited to a certain degree of motions because this material has a high tendency to fracture when prolonging exposure to vibrant environments. In contrast, magnetorheological elastomers (MRE) material has high elasticity properties which could capable to withstand this environment. Thus, this project aimed to use MRE in the development of the linear actuator system and observed its displacement responses. The MRE specimens were fabricated using silicon rubber and magnetic particle with the composition of 70/30, 60/40, 50/50, 40/60, and 30/70 percent by its weight percentage (wt%) using compression moulding technique. The surface morphologies were performed to observe the distribution of the particles. Then, the vision-based measurement system was developed in order to perform a displacement test on the MRE specimens. Besides that, the system is also acting as displacement feedback for MRE linear actuator closed-loop control system. System identification approach was adapted to estimate an MRE linear actuator plant model and then used to tune a proportional integral derivative (PID), controller. Prior testing, a sample of the linear actuator was designed and simulated using SOLIDWORKS 2016 x64 Edition and Finite Element Magnetic Method (FEMM) 4.2, respectively in order to observe the magnetic field. It is observed that magnetic particles distributed on the specimen surface similar to the isotropic types. Besides, the vision-based positioning system developed was reported having an accuracy of up to 0.0025 μm. Furthermore, the highest displacement span was 84 μm, which obtained from composition 50/50 silicon rubber: magnetic particles by its wt%. The experimental result shows that the PID controller successfully reduces a steady-state error (7 μm) and settling time (12s) for MRE linear actuator. According to the finite element analysis, the maximum magnetic density observed at plunger with the value of 1.8 tesla. MRE plant model was successfully developed by 85% fitted to real experimental data. Besides, the PID values for Kp, Ki, and Kd were tuned to 5.26, 5.25 and 0, respectively. As a conclusion, the MRE using silicon rubber and magnetic particle were successfully developed and 50/50 by wt% composition had optimum displacement response. Furthermore, the displacement response for MRE based actuator design used in this research was comparable to the existing linear actuator. The vision-based positioning system developed also can be used as measurement and control the displacement in the actuator application.

2025-09-03T00:00:00Z KHAIRUL AZREEN BIN MOHD ZAINOL AMIR, UniKL MIDI http://hdl.handle.net/123456789/33043 2025-09-03T01:16:26Z 2025-09-03T00:00:00Z

Title: EFFECTIVENESS OF MINIMUM QUANTITY LUBRICATION WHEN POCKET MILLING ALUMINUM ALLOY 7075-T6 WITH CARBIDE TOOLS UNDER HIGH-SPEED MACHINING Authors: KHAIRUL AZREEN BIN MOHD ZAINOL AMIR, UniKL MIDI Abstract: Abstract of thesis presented to the Senate of Universiti Kuala Lumpur Malaysia in fulfillment of the requirements for the Degree of Master in Engineering Technology (Manufacturing) EFFECTIVENESS OF MINIMUM QUANTITY LUBRICATION WHEN POCKET MILLING ALUMINUM ALLOY 7075-T6 WITH CARBIDE TOOL UNDER HIGH-SPEED MACHINING By KHAIRUL AZREEN BIN MOHD ZAINOL AMIR December, 2019 This study outlines the effectiveness of minimum quantity lubrication (MQL) in the pocket milling of aluminum alloy 7075-T6 under high-speed machining (HSM) on tool wear, tool life, surface roughness, and chip morphology. MQL is an environmentally friendly approach where a small amount of cutting fluid was sprayed with air aid to the cutting zone in the mist form. Previous studies have found that tool wear is a major challenge to achieve excellent surface quality, tool performance, and favorable chip formation. The experimental work was performed on the computer numerical control (CNC) five axes milling machine with uncoated carbide tools. The machining parameters with three controlled factors and two levels were designed utilizing full factorial xx design and analysis of variance (ANOVA) was then applied to determine the level of significant machining parameters. Different values of machining parameters involved were 500 and 600 m/min, 0.12 and 0.15 mm/tooth, and 1.40 and 1.70 mm, representing cutting speed, feed rate, and axial depth of cut, respectively. The radial depth of cut of 7 mm was kept constant throughout the experiment. The MQL flow rate was set at 100 mL/h. Dry cutting was done to compare the outcome result with MQL 100 mL/h. After each experiment, the tool flank wear and surface roughness were observed and measured by using an optical microscope and the surface roughness tester, respectively. The tool life criterion was determined when the tool wear failure reached 0.30 mm. The chips collected from all these machining parameters were taken to be examined using an optical microscope. The empirical model of tool life and surface roughness for the MQL and dry cutting was developed with adequate accuracy within the experimental ranges. From the result obtained, MQL 100 mL/h at cutting speed of 500 m/min, feed rate of 0.12 mm/tooth, and axial depth of cut of 1.40 mm stimulated the tool lifespan up to 20.21 minutes. The tool flank wear was observed at all the cutting conditions as a result of adhesion wear mechanism. Uncoated carbide tools with a combination of high cutting speed of 600 m/min and low feed rate of 0.12 mm/tooth produce good surface roughness. At 600 m/min and 0.12 mm/tooth under MQL 100 mL/h, the favorable chip formation was obtained, thus improve surface roughness and diminish severe localization of heat. It is recommended that the flow rate of MQL 100 mL/h should be used for high-speed machining of aluminum alloy 7075-T6 with appropriate machining parameters may potentially lead to economic benefits in terms of fluid cost saving and the better machinability.

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