318 research outputs found
Fabrication of SiC/Magnesium Alloy Composite via Friction Stir Processing
No full textA Master of Science thesis in Mechanical Engineering by Ahmad Z. Naser entitled, "Fabrication of SiC/Magnesium Alloy Composite via Friction Stir Processing," submitted in January 2016. Thesis advisor is Dr. Basil Darras. Soft and hard copy availableOne of the most interesting improvements in the history of materials is composites manufacturing. Because of their ability to improve different mechanical properties of some metals, nanoparticles have been given much attention in the composites community. After the successful use and popularity of Friction Stir Welding (FSW) in many applications worldwide, its latest modification into Friction Stir Processing (FSP) has recently been given a considerable amount of attention. FSP can be considered today as one of the most successful alternatives for fabricating metal matrix composite. In this investigation, a Silicon Carbide (SiC)/magnesium alloy composite was fabricated using FSP. Different combinations of tool rotational and translational speeds (RS and TS) were used throughout the study. The effect of such combination on the thermal profile, micro-hardness, and microstructure was studied and compared. Furthermore, a Response-Surface Methodology was used to develop a model to predict the micro-hardness for FSPed specimens using different combinations of process parameters. FSP of Mg AZ 31B as well as Mg/SiC composite was successfully accomplished using different combinations of tool rotational and translational speeds. Micro-hardness results showed excellent agreement with both the thermal and microstructural analysis. Micro-hardness results of the Mg/SiC composite showed a significant amount of improvement. The developed micro-hardness model was very accurate in predicting the micro-hardness values.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
Investigation of Submerged Friction Stir Welding of Marine-Grade Aluminum Alloy
No full textA Master of Science thesis in Mechanical Engineering by Emad Eldin Mohammed Kishta entitled, "Investigation of Submerged Friction Stir Welding of Marine-Grade Aluminum Alloy," submitted in January 2014. Thesis advisor is Dr. Basil Darras and thesis co-advisor Dr. Farid Abed. Available are both soft and hard copies of the thesis.Friction stir welding is a newly developed welding technique utilized to weld lightweight alloys, such as aluminum alloys. Due to its low melting temperature, welding aluminum has been always challenging using conventional techniques. Friction stir welding can be controlled by different parameters like rotational speed, feed rate and welding medium. In this research, submerged friction stir welding of marine grade aluminum alloy 5083 is investigated. The study is divided into two parts, experimental and numerical investigations. In the experimental part, the effect of different welding parameters on thermal histories, tensile properties and microstructural properties are studied. The numerical part is a finite element modeling of the process to predict the changes in thermal profiles and material properties as the welding parameters are changed. The results of this study show that submerging highly affected the thermal histories and thus the microstructural and mechanical properties of the welded alloy. Controlling both the rotational speed and the feed rate found to be crucial to successfully friction stir weld aluminum and achieving good mechanical properties. The finite element model successfully predicted the thermal profile generated by friction stir welding under different parameters.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
Adoption of Industry 4.0 for Sustainable Manufacturing
No full textA Master of Science thesis in Mechanical Engineering by Parham Dadash Pour entitled, “Adoption of Industry 4.0 for Sustainable Manufacturing”, submitted in April 2022. Thesis advisor is Dr. Mohammad Nazzal and thesis co-advisor is Dr. Basil Darras. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).The Fourth Industrial Revolution (Industry 4.0) intends to help different industries monitor, control, and run their production systems efficiently. Most of the currently available Industry 4.0 implementation frameworks focus on providing users with an implementation plan that do not include information regarding technology selection or readiness assessment. In this work, a comprehensive Industry 4.0 implementation framework is developed to help manufacturing firms improve their current state of production. The framework developed consists of five main stages. These stages are gap analysis, Industry 4.0 technology selection, Industry 4.0 readiness assessment, Industry 4.0 reference architecture selection, and pilot project assessment. An Industry 4.0 technology selection model is developed that uses Fuzzy Analytical Hierarchy Process (FAHP) to assign weights to the production, social, economic, and environmental indicators. Fuzzy Technique for Order of Preference by Similarity to Ideal Solution (FTOPSIS) is used to aggregate the results and rank the technology alternatives based on their scores. Furthermore, a novel Industry 4.0 readiness tool is developed to assess how capable the facility is to implement Industry 4.0 technologies. A case study was carried out by applying the developed Industry 4.0 technology selection and readiness assessment procedures on an aluminium extrusion factory. Cyber-Physical Systems, Big Data Analytics, and Autonomous/Industrial Robots were the top three ranked technologies to be implemented having closeness coefficient scores of 0.964, 0.928, and 0.601, respectively. The firm obtained a readiness score of 45.8% based on the developed readiness assessment model revealing that the firm is at an intermediate readiness level.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
Experimental Investigations of Friction Stir Welded Metal-Polymer Hybrid Structure
No full textA Master of Science thesis in Mechanical Engineering by Ali Abdel Ghani Ali Barakat entitled, “Experimental Investigations of Friction Stir Welded Metal-Polymer Hybrid Structure”, submitted in April 2023. Thesis advisor is Dr. Basil Darras and thesis co-advisor is Dr. Mohammad Nazzal. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).In the last decade, there has been a surge in interest in hybrid structures, particularly those that combine aluminum or magnesium alloys with polymeric materials. Mechanical fastening, riveting, and bonding are examples of traditional methods of joining metals and polymers. However, these methods have several limitations such as extended curing times, low dependability joints, and stress concentration. The fundamental difficulty in combining metals and plastics is the considerable disparity in structure and surface energy between both materials, which is a crucial reason that makes a sound connection difficult to produce. To overcome the limitations of traditional joining methods, a different approach to combining different materials is required. In comparison to traditional methods, friction stir welding as a joining technique for metal-to-polymer hybrid connections is a promising alternative. Recently, there has been a growing interest in research projects aimed at determining the feasibility of employing friction stir welding for joining dissimilar materials. The purpose of this thesis is to investigate friction stir welding of AA6061 aluminum alloy sheets to Polyamide 6 (PA6). In this work, the impact of welding parameters on the mechanical, microstructural, and material flow of the hybrid joint was addressed. A comprehensive evaluation of the process based on a multidimensional sustainability assessment model, as well as comparisons to other conventional joining techniques such as adhesive bonding and self-piercing riveting were addressed.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
Mechanical Behavior of Friction Stir Extruded Tubes
No full textA Master of Science thesis in Mechanical Engineering by Abdulla Taoufik Alhourani entitled, “Mechanical Behavior of Friction Stir Extruded Tubes”, submitted in December 2020. Thesis advisor is Dr. Mohammad Ahmad Hasan Nazzal and thesis co-advisor is Dr. Basil Mohammad Darras. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Friction Stir Back Extrusion (FSBE) is a new grade of severe plastic deformation processes capable of producing metallic tubular geometries that exhibit ultrafine grain structure and superior mechanical properties. FSBE of tubular sections provide opportunities for producing lightweight rigid structures for the automotive, aerospace and construction industries. This research investigates the impact of rotational speed and feed rate on the mechanical properties, power consumption and cycle time for FSBE of Magnesium AZ31-B tubes under air cooling medium to determine the optimal settings. The investigation is conducted utilizing Response Surface Methodology (RSM) and desirability multi-response optimization technique. RSM results suggest that the ultimate tensile strength and toughness are impacted by both rotational speed and feed rate and are more sensitive to spindle rotational speed. Yet, both parameters did not show a significant statistical impact on percent elongation. The optimal settings to maximize mechanical properties and minimize production indicators are 2000 rpm and 116 mm/min. Furthermore, the effect of submerging conditions (in water at 25 °C and 2 °C) on the grain size and mechanical properties was investigated and compared to FSBE in air. It is shown that the impact of submerging is statistically insignificant in terms of the mechanical properties of the produced tubes. On the other hand, finer grains were observed at the inner wall of the tube for FSBE in air and underwater FSBE at 25 °C when compared to underwater FSBE at 2 °C.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
A General Framework for Sustainability Assessment of Manufacturing Processes
No full textA Master of Science thesis in Mechanical Engineering by Mohammed Hassoun Saad entitled, “A General Framework for Sustainability Assessment of Manufacturing Processes”, submitted in November 2018. Thesis advisor is Dr. Basil Darras and thesis co-advisor is Dr. Mohammad Nazzal. Soft and hard copy available.The manufacturing sector has a major impact on the three sustainability dimensions represented by social, economic, and environmental aspects. Most of the work on sustainability assessment in the field of manufacturing is conducted at the product level or for specific processes; mainly machining with a limited number of indicators that do not capture all three dimensions of sustainability. The aim of this work is to develop a new systematic and comprehensive framework for the sustainability assessment of manufacturing processes that covers the three sustainability dimensions. Guidelines to select and quantify the relevant indicators, convert the quantified weighted indicators into dimensionless quantities, and rank the alternatives based on the aggregated scores are presented. The proposed framework combines objective and subjective weighting methods to reduce the uncertainty associated with subjective weighting. It also captures the interaction among different indicators by utilizing multi-criteria decision making methods instead of the traditional statistical methods. Sensitivity analysis is proposed to ensure the reliability and robustness of the aggregated results (final scores). A case study is carried out by applying the proposed framework to evaluate the sustainability level of four welding processes, which are Friction Stir Welding (FSW), Gas Metal Arc Welding (GMAW), Gas Tungsten Arc Welding (GTAW) and Shielded Metal Arc Welding (SMAW). The four processes are used to weld aluminum 5083 plates with a thickness of 5 mm. Physical performance of the welded plates is considered as a fourth sustainability dimension to assess the quality of the welded parts. The assessment is carried out using three multi-criteria decision making methods, which are the TOPSIS, GRA and COPRAS. The results obtained from the assessment reflect that the FSW welding is the most sustainable welding process for this case with an overall sustainability score of 0.611 based on TOPSIS method, 0.753 based on GRA, and 0.317 based on the COPRAS method.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
Sustainability Assessment of Welding Processes
No full textA Master of Science thesis in Mechanical Engineering by Jaber Jamal entitled, "Sustainability Assessment of Welding Processes," submitted in May 2017. Thesis advisor is Dr. Basil Darras and thesis co-advisor is Dr. Hossam Kishawy. Soft and hard copy available.In today's world, calls for 'sustainability' are increasing in order to preserve our resources and our environment. Many initiatives are being put in motion to make our lives more 'sustainable'. This concept of 'sustainability' has recently risen to take the old concept of going 'green' further. To elaborate, where 'green' aimed to preserve the environment and decrease the emissions of greenhouse gases and other harmful substances, 'sustainability' takes the economy and society into consideration. This is done by considering how much money it would cost, how it would affect the society, and how to be more environmentally friendly for a particular product or process. This thesis aims to outline general methodologies for sustainability assessments. This would then be adapted for manufacturing processes, and then would be applied to measure and assess the sustainability of welding processes. The objective is to build a complete framework that would be used to determine the best welding process for a particular application. To apply this methodology, data about the welding processes was collected and segregated into four categories: environmental impact, economic impact, social impact, and physical performance. Each of these categories had a number of indicators which would quantify the performance of each process. This quantification step was done by developing specific equations and applying them to the indicators. An aggregate sustainability score was then obtained from the individual scores of each category. However, to avoid taking the arithmetic average which indicates equal importance for each category, a weighted average was suggested in this thesis. To obtain the respective weights, a survey was created and distributed to experts. The collected results were analyzed and incorporated to calculate the aggregate score. To demonstrate the capability of this methodology, three welding processes, gas tungsten arc welding (GTAW), gas metal arc welding (GMAW), and friction stir welding (FSW) were assessed on welding Aluminum 5083. This would determine the most sustainable process in that particular application. The final outcome showed that FSW was the most sustainable process for the application.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
Modeling of Friction Stirring
No full textA Master of Science thesis in Mechanical Engineering by Mohamed Anass Abdalla Badreldin entitled, “Modeling of Friction Stirring”, submitted in November 2018. Thesis advisor is Dr. Mohammad Nazzal and thesis co-advisor is Dr. Basil Darras. Soft and hard copy available.The last two decades have witnessed significant advances in friction stir welding (FSW). This solid-state welding process was originally used for joining Aluminum alloys before being extended to other metallic and non-metallic materials. The high complexity in FSW stems from the complex interactions between highly coupled physical phenomena. As experimental procedures are costly and time-consuming, numerical simulations were used extensively in an effort to develop a comprehensive understanding of the process. This research consists of two parts: one part provides a critical review of the three fundamental components of the numerical simulation of FSW; which are the numerical method, the constitutive model, and the contact model. The second part contains the detailed development of the finite element model to study the FSW process and submerged FSW process (SFSW), with emphasis on the effect of submerging on the temperature profile and thermal history. The finite element model is developed using the Coupled Eulerian-Lagrangian modeling technique and is validated against previous experimental work for the Aluminum 5083 alloy. Temperature profiles for different welding conditions are investigated to validate the model. The developed finite element model is able to predict the temperature profile in both FSW and SFSW processes. It also captures the dissymmetrical temperature distribution around the welding line; and the effect of using the SFSW process on peak temperatures, cooling rates, and size of the heat affected zone. Moreover, flash formation and the material flow patterns are successfully captured. The results show that increasing the rotational speed from 1000 rpm to 1700 rpm for the SFSW of the Aluminum 5083 alloy resulted in an increase in peak temperature by 200%. This temperature rise yields to material softening, improved the material flow, and higher weld quality.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
CFD Study of Particle Concentration and Stokes Number Effect on Erosion Profile.
No full textA Master of Science thesis in Mechanical Engineering by Wahib Mufid Salim entitled, "CFD Study of Particle Concentration and Stokes Number Effect on Erosion Profile," submitted in April 2017. Thesis advisor is Dr. Basil Darras and thesis co-advisor is Dr. Ammar Abdilghanie. Soft and hard copy available. Embargo expires February 18, 2018.A very common problem that continuously faces industrial applications involving fluid flow is solid particle erosion. This type of erosion is caused when solid particles carried by a fluid flow continuously impact a surface thus removing some of its material. It is especially notable in pipelines, oil and gas industry, and gas turbines leading to a decline in their performance, safety, and other aspects. Consequently, it is very important to be able to predict erosion in order to prevent failure of systems, protect the environment, and reduce costs. However, erosion is controlled by many parameters, which increase the complexity of the problem. Literature tends to provide sufficient information on how these parameters affect total erosion and erosion rate. On the other hand, it does not give enough analysis about the effect on the erosion profile. Therefore, this thesis aims at performing a parametric study on the effect of solid particle concentration and Stokes number on the erosion profile of a direct jet impingement slurry flow over a ductile material. A CFD (Computational Fluid Dynamics) model was developed using ANSYS CFX software to perform the needed analysis. The Stokes number was evaluated by looking at three of its defining parameters: solid particle diameter, nozzle average velocity and fluid viscosity. Additionally, the coupled effect of solid particle concentration and Stokes number was studied. It was found that as concentration increases, the erosion profile magnitude also increases but the change in its shape tends to saturate. However, it was also found that the effect of Stokes number on magnitude and shape of the erosion profile is dependent on the level of particle concentration and which defining parameter is under investigation. At low concentration, the change in profile shape saturates with increase in Stokes number when varying the nozzle average velocity and viscosity parameters; whereas, when evaluating the solid particle diameter,the shape tends to develop into a that of a high Stokes flow. However, at high concentration, the profile shape significantly grows into that of a high Stokes flow as the Stokes number increases when varying any of the three defining parameters.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
Electric Vehicle Batteries’ Lifecycle Management
No full textA Master of Science thesis in Mechanical Engineering by AbdulRahman Salem entitled, “Electric Vehicle Batteries’ Lifecycle Management”, submitted in October 2025. Thesis advisor is Dr. Basil Darras and thesis co-advisor is Dr. Mohammad Nazzal. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).The global transition toward clean energy caused the automotive industry to embrace electric vehicle (EV) production. EVs using clean renewable energy are expected to have significantly lower environmental impact compared to conventional internal combustion vehicles. However, the recycling of EV batteries causes several environmental issues. For instance, the disposal of leaching solutions used in leaching lithium from Li-ion batteries causes soil and water eutrophication. Furthermore, pyrolysis of battery packaging and Printed Circuit Boards (PCBs) containing polymers releases toxic polybrominated fumes, dioxins and furans to the environment. Moreover, most EV batteries are disposed of without utilizing their full potential. EV batteries become unfit for EV use once they lose 20% of their original capacity, which leaves 80% of their capacity untapped. To address these issues, this research developed three decision making frameworks. The first framework provides a blueprint to identify Key Performance Indicators (KPIs) and the decision making process for the selection of battery State of Health (SOH) estimation models responsible for determining EV batteries’ viability for second use options. The second framework introduces a general EV battery management system presented a sorting mechanism capable of 98% sorting consistency, superior to contemporary machine learning models (85 – 90%) used in EV battery health monitoring and management frameworks. Additionally, the sorting framework utilizes a QR code-based Matlab program to identify battery KPIs and assign them accordingly to their appropriate end destination in either renewable energy applications or refurbishing and recycling centers. Moreover, this framework outlines the line of interaction between users, manufacturers and governments to facilitate handling and retrieval of end-of-life EV batteries. Lastly, a third framework was developed to facilitate battery material selection for future EV applications based on holistic KPIs identified from scientometric analysis and literature review of battery material technology advance ments. Multiple case studies validated the flexibility, robustness, and effectiveness of the proposed frameworks in decision-making and end-of-life battery management. The frameworks can be adopted by government entities for sorting used and spent EV batteriesCollege of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
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