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Full-Text Articles in Mechanical Engineering

Comparison Of The Thermal Stability In Equal-Channel-Angular-Pressed And High-Pressure-Torsion-Processed Fe–21cr–5al Alloy, Maalavan Arivu, Andrew Hoffman, Jiaqi Duan, Jonathan Poplawsky, Xinchang Zhang, Frank Liou, Rinat Islamgaliev, Ruslan Valiev, Haiming Wen Nov 2023

Comparison Of The Thermal Stability In Equal-Channel-Angular-Pressed And High-Pressure-Torsion-Processed Fe–21cr–5al Alloy, Maalavan Arivu, Andrew Hoffman, Jiaqi Duan, Jonathan Poplawsky, Xinchang Zhang, Frank Liou, Rinat Islamgaliev, Ruslan Valiev, Haiming Wen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Nanostructured steels are expected to have enhanced irradiation tolerance and improved strength. However, they suffer from poor microstructural stability at elevated temperatures. in this study, Fe–21Cr–5Al–0.026C (wt.%) Kanthal D (KD) alloy belonging to a class of (FeCrAl) alloys considered for accident-tolerant fuel cladding in light-water reactors is nanostructured using two severe plastic deformation techniques of equal-channel angular pressing (ECAP) and high-pressure torsion (HPT), and their thermal stability between 500–700 °C is studied and compared. ECAP KD is found to be thermally stable up to 500 °C, whereas HPT KD is unstable at 500 °C. Microstructural characterization reveals that ECAP KD …


An Investigation Into The Challenges Of Contemporary Additive Manufacturing: Insights Into The Metallurgical Response Of Materials And Relevant Solution, Huan Ding Nov 2023

An Investigation Into The Challenges Of Contemporary Additive Manufacturing: Insights Into The Metallurgical Response Of Materials And Relevant Solution, Huan Ding

LSU Doctoral Dissertations

Additive Manufacturing (AM) has gained attention in recent years due to its unique capabilities in the fabrication of complex parts. As with any new research, there is still a lack of sufficient understanding in the field of additive manufacturing, and further investigation is needed to solve existing problems. Ultimately, the aim is to enable the widespread use of AM components across various industries.

Chapter One provides a brief introduction to the background and current bottlenecks of additive manufacturing technology. Chapter two focuses on the development of high-strength 7075 aluminum alloy (Al7075) for Fused Deposition Modeling and Sintering (FDMS) technology. Al7075 …


Analysis Of Bombyx Mori Silk And Polyimide Nanofibers, Sabrina Leseul Nov 2023

Analysis Of Bombyx Mori Silk And Polyimide Nanofibers, Sabrina Leseul

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

This thesis presents a study on the properties of Bombyx Mori silk nanofibers and polyimide (PI) nanofibers. Firstly, a Bombyx Mori silk solution has been created with degummed silkworm cocoons in order to separate the fibroin and the sericin, the two main proteins of the silk. The fibroin was then centrifuged to remove insoluble particles and stored and 4°C before mixing with hexafluoroisopropanol (HFIP). On the second part, a polyimide solution, made with shavings of polyimide and N,N-dimethylformamide (DMF). Both solutions are then electrospun. Electrospinning parameters are studied. In this way, a part of my thesis has been dedicated to …


Applications Of Femtosecond Laser-Processed And Nanoneedle-Synthesized Surfaces To Enhance Pool Boiling Heat Transfer, Peter Efosa Ohenhen Nov 2023

Applications Of Femtosecond Laser-Processed And Nanoneedle-Synthesized Surfaces To Enhance Pool Boiling Heat Transfer, Peter Efosa Ohenhen

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

In the present work, the integration of femtosecond laser surface processing (FLSP) with copper hydroxide on hybrid surfaces was examined. The goal was to determine the impact on pool boiling enhancement. The samples for the investigation were fabricated by first functionalizing with FLSP, and the process was then followed by citric acid cleaning (CAC) to eliminate the oxides generated on the copper surface during the FLSP process. After the citric acid cleaning, the samples were immersed in ethanol and subjected to an ultrasonic bath for 25 minutes. This step was performed to eliminate any residual citric acid and loose particles. …


Impact Of Silicon Ion Irradiation On Aluminum Nitride-Transduced Microelectromechanical Resonators, David D. Lynes, Joshua Young, Eric Lang, Hengky Chandrahalim Nov 2023

Impact Of Silicon Ion Irradiation On Aluminum Nitride-Transduced Microelectromechanical Resonators, David D. Lynes, Joshua Young, Eric Lang, Hengky Chandrahalim

Faculty Publications

Microelectromechanical systems (MEMS) resonators use is widespread, from electronic filters and oscillators to physical sensors such as accelerometers and gyroscopes. These devices' ubiquity, small size, and low power consumption make them ideal for use in systems such as CubeSats, micro aerial vehicles, autonomous underwater vehicles, and micro-robots operating in radiation environments. Radiation's interaction with materials manifests as atomic displacement and ionization, resulting in mechanical and electronic property changes, photocurrents, and charge buildup. This study examines silicon (Si) ion irradiation's interaction with piezoelectrically transduced MEMS resonators. Furthermore, the effect of adding a dielectric silicon oxide (SiO2) thin film is …


Top-Down Nanomanufacturing Of Anisotropic Two-Dimensional Metals, Md Rubayat-E Tanjil Oct 2023

Top-Down Nanomanufacturing Of Anisotropic Two-Dimensional Metals, Md Rubayat-E Tanjil

USF Tampa Graduate Theses and Dissertations

Two-dimensional (2D) materials have introduced a transformative era in materials science with extensive research being performed to gain a fundamental understanding of their diverse properties and applications. Amongst the broader 2D material family, 2D metals or 2D metallic nanosheets (2DMNSs) typically denotes the nanometer-scale thin elemental metals, compound, or alloys, which shows superlative chemical and physical properties compared to bulk counterparts due to the reduced dimensionality. 2D materials’ widespread direct physical or chemical isolation techniques have been facilitated due to their intrinsic van der Waals layered morphology, whereas 3D close-packed bulk metals with isotropic bonding hinder their facile isolation in …


Structural Health Monitoring And Repair Of Welded Thermoplastic Composite Joints Using Embedded Multifunctional Films, Wencai Li Oct 2023

Structural Health Monitoring And Repair Of Welded Thermoplastic Composite Joints Using Embedded Multifunctional Films, Wencai Li

LSU Doctoral Dissertations

Thermoplastic composites (TPCs) have gained widespread use, particularly in large or integrated structural components, necessitating effective joining techniques. Fusion bonding (welding) has emerged as a suitable method for TPCs due to their ability to be reshaped through heating and cooling, eliminating the need for mechanical fasteners, long curing times, and extensive surface preparation. Among the welding techniques, ultrasonic welding (USW) stands out for its fast-cycling time and potential for automating large-scale structures, thereby reducing energy consumption. However, limited industrial applications of USW in this context require further knowledge to instill confidence in the process. Moreover, composite structures are susceptible to …


Effect Of Fire Flame On Some Mechanical Properties Of Self-Compacting Concrete, Haider Sadiq M. Ali, Nabeel A-M. Albayati, Basman R. Mohammed, Adil M. Jabbar Oct 2023

Effect Of Fire Flame On Some Mechanical Properties Of Self-Compacting Concrete, Haider Sadiq M. Ali, Nabeel A-M. Albayati, Basman R. Mohammed, Adil M. Jabbar

Al-Esraa University College Journal for Engineering Sciences

This paper presents an experimental investigation of the effect of fire flame on self-compacting concrete. The experimental program included casting cylinder and prism concrete specimens for compressive strength, modulus of elasticity, modulus of rupture, and concrete density tests. The specimens are exposed to fire flame at 800 ºC approximately for 2 hours or 6 hours. Then the specimens were cooled either in a fast or slow manner. Test results show that the compressive strength was reduced by about (54 - 61)% for fire exposure of 6 hours and by (27 - 37)% for 2 hours of exposure and cooled slowly …


Manual Preparation Of Eyeglasses Based On Corneal Topographical Images For Keratoconus Patients, Bassma Sabah Majeed, Faiz F. Mustafa, Nebras H. Ghaeb Oct 2023

Manual Preparation Of Eyeglasses Based On Corneal Topographical Images For Keratoconus Patients, Bassma Sabah Majeed, Faiz F. Mustafa, Nebras H. Ghaeb

Al-Esraa University College Journal for Engineering Sciences

keratoconus (KCN) is a non-inflammatory, progressive thinning process of the cornea. It is considered one of the advanced biomechanical changes on the corneal surface, and methods of treatment in late cases are special designed contact lenses or surgical intervention. The objective of this paper is to customize the standard eyeglass lens in a way so that it fits with the abnormal shape and changes of the surface of the cornea of a patient suffering from KCN disease.The proposed method here, based on manual scratching of the external surface of the standard eyeglass lens under supervising of an expert optometrist, where …


Age-Friendly Educational Buildings Primary Schools In Kerbala - A Case Study, Anwar Fadhil Hussein, Ibrahim Jawad Kadhim Oct 2023

Age-Friendly Educational Buildings Primary Schools In Kerbala - A Case Study, Anwar Fadhil Hussein, Ibrahim Jawad Kadhim

Al-Esraa University College Journal for Engineering Sciences

The concept of age-friendly societies has gained international attention among researchers, policy makers, and community organizations since the World Health Organization launched the Friendly Communities Project in 2006, to address challenges in some countries, as these challenges affect all aspects of society, and the educational environment represents an important joint of those joints, being the environment that is the most effective and influential in shaping human behavior. The age stage that is most affected and capable of learning and shaping behavior is of importance, which is the childhood stage. Therefore, the research focused on school buildings, as they represent an …


The Role Of Enhancing Interaction With The Natural Environment In Achieving Social Interaction For Children In Orphanage Institutions, Shamael M. W. Al Dabbagh, Zainab Khalid Rashad Al Khafaji Oct 2023

The Role Of Enhancing Interaction With The Natural Environment In Achieving Social Interaction For Children In Orphanage Institutions, Shamael M. W. Al Dabbagh, Zainab Khalid Rashad Al Khafaji

Al-Esraa University College Journal for Engineering Sciences

The child deprived of family care is considered the child most in need of attention and care. When the orphan child enters a new environment for him, it is obvious that he feels alienated, isolated, and loses the sense of interaction and communication with society. The research sees the possibility of mitigating this feeling by enhancing interaction with the natural environment within the internal spaces of the orphanage building and at the neighborhood level. In order to solve the research problem, the research adopted a hypothesis stating that "interaction with the natural environment enhances the achievement of social interaction for …


The Role Of Academic Competitions In Promoting Architectural Education: Tamayouze Excellence Award In Iraqi Architectural Education - Case Study, Nairy Mugardich Krikor, Anwar Subhi Ramadan Oct 2023

The Role Of Academic Competitions In Promoting Architectural Education: Tamayouze Excellence Award In Iraqi Architectural Education - Case Study, Nairy Mugardich Krikor, Anwar Subhi Ramadan

Al-Esraa University College Journal for Engineering Sciences

The importance of architectural competitions has emerged in finding the best designs, upgrading and architectural advancement in both practice and thinking. Architectural competitions have become intellectual meetings that contribute to stimulating self-learning and encouraging creativity. They act as an educational tool that leads to competition, giving motivation to the development of skills and learning, in a way that enhances the integration between architectural theory and practical practice for both engineers and architecture students. The research was concerned with studying the effective role of academic competitions in architectural education as one of the ways to improve teaching and learning, and to …


Analysis And Mitigation Of Cyber-Attacks Targeting Infrastructures Operated By Iot Systems, Raja Salih Mohammed Hasan, Nadia Mahmood Ali, Ihsan Jabbar Hasan Oct 2023

Analysis And Mitigation Of Cyber-Attacks Targeting Infrastructures Operated By Iot Systems, Raja Salih Mohammed Hasan, Nadia Mahmood Ali, Ihsan Jabbar Hasan

Al-Esraa University College Journal for Engineering Sciences

Numerous countries have a high impact on providing the planet with critical infrastructures offering very important services employed in different fields such as water resources management, public services, power grids, telecoms, commercials, and transportation. The increasing solutions in IoT systems made it possible to exploit internet connection services for supporting the critical infrastructures. The latest are being targeted by various types of cyber-attacks due to the advancement in internet services. Therefore, improving the security systems and the ways to detect the threats is highly required. Meanwhile, protecting the critical infrastructures from hostile cyber-attacks is of high significance. This article examines …


Reliability Assessment Model Of Network Operating System Based On Convolution Neural Network, Jamal N. Hasoon, Sarah S. Qasim, Mohammed A. Alshomali, Jane J. Stephan Oct 2023

Reliability Assessment Model Of Network Operating System Based On Convolution Neural Network, Jamal N. Hasoon, Sarah S. Qasim, Mohammed A. Alshomali, Jane J. Stephan

Al-Esraa University College Journal for Engineering Sciences

The paper's subject is one of the points of fundamental significance in improving the development of complex computer systems is the effect of errors since their probability of occurrence in a widely distributed system is exceptionally high. Thus, the computer system must be dependable and provide comprehensive support for fault tolerance, fault detection, signal recovery mechanisms, failure prediction, etc. The goal is to develop a way to evaluate the reliability of the Red Hat Linux operating system utilizing data sets of system failures obtained from system injection with error reports using the Fault Injection Benchmarking and Reliability) FIBR( (for a …


Investing Traditional Architecture That Fulfills The Supreme Human Needs With Its Spiritual Dimension In Reconstruction / The Architecture Of Old Mosul City, A Case Study, Sinan Mohammad Talee Al-Saffar, Anwar Subhi Ramdan Al - Qaraghuli Oct 2023

Investing Traditional Architecture That Fulfills The Supreme Human Needs With Its Spiritual Dimension In Reconstruction / The Architecture Of Old Mosul City, A Case Study, Sinan Mohammad Talee Al-Saffar, Anwar Subhi Ramdan Al - Qaraghuli

Al-Esraa University College Journal for Engineering Sciences

Architecture has sought since time immemorial to meet multiple human needs, starting from the basic physiological needs for human survival, psychological needs (social and individual) to needs related to human progress, such as taking into account the aesthetic and spiritual aspects, which represent the highest levels of those needs, through a set of design aspects and characteristics. This research is based on the study of the spiritual dimension of higher human needs in general that architecture seeks to meet, by studying that in the architecture of traditional cities, in particular, to enhance architectural knowledge with regard to the importance of …


The Role Of Algorithms In Formulating The Architectural Formation, Ghada Ghalib Abdul Wahab, Younis Mahmood M. Salem Oct 2023

The Role Of Algorithms In Formulating The Architectural Formation, Ghada Ghalib Abdul Wahab, Younis Mahmood M. Salem

Al-Esraa University College Journal for Engineering Sciences

Algorithms are mathematical processes that provide step-by-step instructions for solving a specific problem. They are commonly used in computer science and other technical fields to automate processes and solve complex problems. One great application of algorithms is the generation of shapes. Algorithms can be used to create complex shapes and patterns that are difficult or impossible to create manually. We will explore how algorithms can be used as a mechanism to generate shapes by adopting the Voronoi algorithm because it provides a wide environment for creativity through new intellectual processes that may not occur at all in the human mind …


The Detection Of Android Malwares Using The Features Selection Technique, Farah Rafid Salman, Amer Abdulmajeed Abdulrahman Oct 2023

The Detection Of Android Malwares Using The Features Selection Technique, Farah Rafid Salman, Amer Abdulmajeed Abdulrahman

Al-Esraa University College Journal for Engineering Sciences

The use of Android smartphones has been rising quickly as Internet-based services gain more popularity and develop. The Android operating system's enormous popularity has drawn malware attacks on these devices. It is difficult and ineffective to detect malware versions with features that modify their behavior in order to avoid detection by machine learning (ML) techniques. Effective feature selection plays a crucial role in detecting malware characteristics and reduces the dimensionality of a large dataset by removing unnecessary features that are not useful and keeping those relevant features that increase classification accuracy and detection rate. This helps to solve the problems …


A Review Of Polymer – Particles Composite Materials, Ismail Ibrahim Marhoon, Ayad Abbood Abdul Al-Hassan, Mohammed Ali Abdulrehman Oct 2023

A Review Of Polymer – Particles Composite Materials, Ismail Ibrahim Marhoon, Ayad Abbood Abdul Al-Hassan, Mohammed Ali Abdulrehman

Al-Esraa University College Journal for Engineering Sciences

In several engineering applications traditional materials are replacedby composite materials. Filled composite materials consist of the continuousmatrix and the filling particles. The primary purpose of introducing inorganicsolid particles into polymers is to essentially increase mechanical and physicalproperties. The wear properties of polymer composite can be changed to agreater degree by modifying the process of preparing the filled compositematerials. In the present review, a large-scale research has been conductedon the effect of wear on the composites of polymers. The effect of filler onthe polymer composites wear behavior has been thoroughly explained


Ability Of Replacing The Steel Strands By Cfrp In Pre-Stressed Concrete Girders: Art Review, Ahmed Salim Edan, Wael Shawky Abdulsahib Oct 2023

Ability Of Replacing The Steel Strands By Cfrp In Pre-Stressed Concrete Girders: Art Review, Ahmed Salim Edan, Wael Shawky Abdulsahib

Al-Esraa University College Journal for Engineering Sciences

Fiber-reinforced polymer (FRP) composites are the modern,trustworthy alternatives to steel tendons and rebars. The bulk of currentresearch is devoted to establishing the feasibility of incorporating carbonfibre-reinforced polymer (CFRP) into reinforced concrete girders byevaluating the strength and reliability of CFRP and concrete components.In order to improve fatigue and corrosion resistance, CFRPs are crucial.Comparing reinforced prestressed concrete bridge girders strengthenedwith conventional steel reinforcement to those reinforced with CFRPs offersthe possibility of greatly increasing service life. Also widely researchedand used in bridge engineering as a corrosion-resistant substitute for steelreinforcement is CFRP composite material. The use of carbon fiber-reinforcedplastic (CFRP) reinforcement for prestressing concrete …


A Review Article On The Performance Based Seismic Design Of Structures, Reem Hatem Ahmed, Sahar Elaiwi, Shelan Hameed Ameen Oct 2023

A Review Article On The Performance Based Seismic Design Of Structures, Reem Hatem Ahmed, Sahar Elaiwi, Shelan Hameed Ameen

Al-Esraa University College Journal for Engineering Sciences

For the most part, seismic design builds complex structural systems using the same small number of essential structural components as non-seismic design projects. Based on the building regulations, structures are frequently designed to "withstand" the largest earthquake with a given likelihood that is projected to happen at their location. This means that by avoiding structures from collapsing, the number of fatalities must be maintained to a minimal. Seismic design involves knowing the many failure modes regarding a structure and giving it the right stiffness, strength, ductility, and layout for ensuring that these modes do not take place. In this essay, …


Evolution Of Glassy Carbon Derived From Pyrolysis Of Furan Resin, Josh Kemppainen, Ivan Gallegos, Aaron Krieg, Jacob R. Gissinger, Kristopher E. Wise, Margaret Kowalik, Julia A. King, S. Gowtham, Adri Van Duin, Gregory Odegard Oct 2023

Evolution Of Glassy Carbon Derived From Pyrolysis Of Furan Resin, Josh Kemppainen, Ivan Gallegos, Aaron Krieg, Jacob R. Gissinger, Kristopher E. Wise, Margaret Kowalik, Julia A. King, S. Gowtham, Adri Van Duin, Gregory Odegard

Michigan Tech Publications

Glassy carbon (GC) material derived from pyrolyzed furan resin was modeled by using reactive molecular dynamics (MD) simulations. The MD polymerization simulation protocols to cure the furan resin precursor material are validated via comparison of the predicted density and Young's modulus with experimental values. The MD pyrolysis simulations protocols to pyrolyze the furan resin precursor is validated by comparison of calculated density, Young's modulus, carbon content, sp carbon content, the in-plane crystallite size, out-of-plane crystallite stacking height, and interplanar crystallite spacing with experimental results from the literature for furan resin derived GC. The modeling methodology established in this work can …


Cellulose Materials For Drug Delivery Applications, Reham Mohamed Oct 2023

Cellulose Materials For Drug Delivery Applications, Reham Mohamed

Mechanical Engineering Theses

Non-healing wounds are a growing global public health concern due to inadequate or ineffective therapeutic products available. Cellulose-based biopolymers are attractive wound dressing materials due to their biocompatibility, biodegradability, non-toxicity, and cost-effectiveness. This study aims to design and fabricate solid dosage formulations using carboxymethyl cellulose (CMC) and ethyl cellulose (EC) to facilitate multi-stage releases of phenytoin (PHT) and tetracycline hydrochloride (TCH) from plain carriers, fibers/films composites, and layer-by-layer fiber composites. Results from in vitro drug release assays demonstrated a time-dependent release up to 8 hours from PHT-loaded EC fibers, while TCH-loaded CMC films exhibited a rapid release within 5 minutes. …


Fabrication Of Smooth Sac305 Thin Films Via Magnetron Sputtering And Evaluations Of Microstructure, Creep, And Electrical Resistivity, Manish Ojha Oct 2023

Fabrication Of Smooth Sac305 Thin Films Via Magnetron Sputtering And Evaluations Of Microstructure, Creep, And Electrical Resistivity, Manish Ojha

Mechanical & Aerospace Engineering Theses & Dissertations

SAC305 (96.5%Sn-3%Ag-0.5%Cu) is the leading alternative to the traditional Sn-Pb solder eutectic alloy owing to its low melting temperature, better compatibility with other components, and excellent mechanical/structural properties. In the realm of modern electronics, where devices are increasingly miniaturized, the design and characterization of thin solder joints become paramount. The orientation and size of the grains within the solder can influence its ability to withstand mechanical stresses. However, research on SAC thin films remains sparse, and these films present unique challenges and characteristics compared to their bulk counterparts, influenced by factors like interfaces, stresses, thickness, microstructure, and the nature of …


Additive Manufacturing For Medical Education, Michael Noon Oct 2023

Additive Manufacturing For Medical Education, Michael Noon

College of Engineering Summer Undergraduate Research Program

A growing body of evidence is suggesting that anatomical knowledge, the keystone of many medical specialties, is suffering among new graduates. While a host of reasons are provided, one common thread that many point to is the decline of cadaver dissections in the classroom. Many virtual audio-visual tools are used to address this gap, yet evidence has shown their ineffectiveness. Given this gap, the high degree of flexibility found in additive manufacturing (AM), and the many uses AM has already found in the medical field, we propose its use to fill this gap, allowing for students to learn with touch …


The Effect Of Through Thickness Reinforcement Angle On The Disbonding Behavior In Skin-Stringer Configuration, Christopher John Morris Oct 2023

The Effect Of Through Thickness Reinforcement Angle On The Disbonding Behavior In Skin-Stringer Configuration, Christopher John Morris

Mechanical & Aerospace Engineering Theses & Dissertations

Post-cure through thickness reinforcement is a method used to increase the mechanical properties of composite laminates in the transverse direction. This study conducted a test on skin-stringer structures bonded together in three configurations using an epoxy or thermoplastic adhesive at the interface with reinforcing pins inserted through the laminate thickness located at the edge of the stringer at differing angles between -30º and 30º. The fabrication of these samples in configurations B and C consisted of the use of carbon fiber prepeg laminate at a ply orientation of [02902]2s for the skin and [0 90] …


Fatigue Behavior Of Cu-Zr Metallic Glasses Under Cyclic Loading, Nikolai Priezjev Sep 2023

Fatigue Behavior Of Cu-Zr Metallic Glasses Under Cyclic Loading, Nikolai Priezjev

Mechanical and Materials Engineering Faculty Publications

The effect of oscillatory shear deformation on the fatigue life, yielding transition, and flow localization in metallic glasses is investigated using molecular dynamics simulations. We study a well-annealed Cu-Zr amorphous alloy subjected to periodic shear at room temperature. We find that upon loading for hundreds of cycles at strain amplitudes just below a critical value, the potential energy at zero strain remains nearly constant and plastic events are highly localized. By contrast, at strain amplitudes above the critical point, the plastic deformation is gradually accumulated upon continued loading until the yielding transition and the formation of a shear band across …


Establishing Physical And Chemical Mechanisms Of Polymerization And Pyrolysis Of Phenolic Resins For Carbon-Carbon Composites, Ivan Gallegos, Josh Kemppainen, Jacob R. Gissinger, Malgorzata Kowalik, Adri Van Duin, Kristopher E. Wise, S. Gowtham, Gregory Odegard Sep 2023

Establishing Physical And Chemical Mechanisms Of Polymerization And Pyrolysis Of Phenolic Resins For Carbon-Carbon Composites, Ivan Gallegos, Josh Kemppainen, Jacob R. Gissinger, Malgorzata Kowalik, Adri Van Duin, Kristopher E. Wise, S. Gowtham, Gregory Odegard

Michigan Tech Publications

The complex structural and chemical changes that occur during polymerization and pyrolysis critically affect material properties but are difficult to characterize in situ. This work presents a novel, experimentally validated methodology for modeling the complete polymerization and pyrolysis processes for phenolic resin using reactive molecular dynamics. The polymerization simulations produced polymerized structures with mass densities of 1.24 ± 0.01 g/cm3 and Young's moduli of 3.50 ± 0.64 GPa, which are in good agreement with experimental values. The structural properties of the subsequently pyrolyzed structures were also found to be in good agreement with experimental X-ray data for the phenolic-derived carbon …


Optimizing Mn-Al Permanent Magnet Performance Through Control Of The Phase Transformation, Ternary Element Addition, And Advanced Processing, Thomas R. Keller Sep 2023

Optimizing Mn-Al Permanent Magnet Performance Through Control Of The Phase Transformation, Ternary Element Addition, And Advanced Processing, Thomas R. Keller

Dartmouth College Ph.D Dissertations

The growing need for electrical power in machines and vehicles brings with it a growing need for critical materials. The current high-performance permanent magnets (PMs) based on rare-earth (RE) elements Nd and Sm cannot escape the problem of raw material cost, geographic scarcity in the earth’s crust, and lack of circular global supply chains. This poses a problem of industrial ecology: can PMs be made from inexpensive, more abundant materials while still meeting sufficient performance criteria? PMs based on the magnetic τ phase of Mn-Al offer a possible alternative to REPMs. However, years of innovation have not yet achieved real-world …


Challenges In Optimization For The Performance On Sustainability Dimensions In Reverse Logistics Social Responsibility, Sumarsono Sudarto, Katsuhiko Takahashi, Mochammad Dewo Aug 2023

Challenges In Optimization For The Performance On Sustainability Dimensions In Reverse Logistics Social Responsibility, Sumarsono Sudarto, Katsuhiko Takahashi, Mochammad Dewo

Makara Journal of Technology

Reverse logistics social responsibility is preferred as the most acceptable solution for addressing the challenges in stakeholders’ debate regarding social responsibility in supply chains because it involves as many actors as possible in the supply chain to perform social responsibility to achieve sustainability. This paper explores the challenges in achieving optimal policies in sustainability dimensions for collection and recycling facilities in reverse logistics. Sustainability dimensions include economic, environmental, and social aspects. The reverse logistics is modeled on System Dynamics, and a simplified statistical analysis using a contour chart is employed in numerical experiments. Results show a narrow area of optimal …


Influence Of Forming Forces On Torsional, Tensile, And Compressive Deformation Of Paperboard Packages, Arvo Niini, Panu Tanninen, Juha Varis, Ville Leminen Aug 2023

Influence Of Forming Forces On Torsional, Tensile, And Compressive Deformation Of Paperboard Packages, Arvo Niini, Panu Tanninen, Juha Varis, Ville Leminen

Journal of Applied Packaging Research

Paperboard packages were tested mechanically to investigate influence of forming forces on torsional, tensile, and compressive deformation. The packages were paperboard trays which were press formed with different pressing forces and blank holder forces. Deformation of the trays was observed with torsion, compression, and tensile tests. A statistical analysis of test results was conducted to derive optimal forming forces. Increased pressing force yielded desirable deformation characteristics with the trays. Blank holder force had largest impact on the compressive deformation. Interaction of the pressing force and the blank holder force influenced the torsional and the compressive deformation. The optimal forming forces …