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Full-Text Articles in Engineering

Carbon Fibers Recycling From Degraded Prepregs And Mechanical Properties Or Recycled Composite, Monjur Morshed Rabby, Minhazur Rahman, Partha Pratim Das, Vamsee Vadlamudi, Rassel Raihan Apr 2023

Carbon Fibers Recycling From Degraded Prepregs And Mechanical Properties Or Recycled Composite, Monjur Morshed Rabby, Minhazur Rahman, Partha Pratim Das, Vamsee Vadlamudi, Rassel Raihan

Institute of Predictive Performance Methodologies (IPPM-UTARI)

The size of the global composites market is anticipated to grow more than previously. Due to the rapidly rising volume of CFRP production, the waste from this material poses numerous problems and has significantly increased the socio-technological pressure to find sustainable composite recycling solutions. The problem is that recycling the composite part is challenging once its service life has expired. The same problem is true for the raw materials (prepregs) used in composite manufacturing. When the prepreg out-life/shelf-life is over, prepregs are abandoned, resulting in a loss of millions of dollars and an adverse environmental effect. In this study, the …


Artificial Intelligence Assisted Residual Strength And Life Prediction Of Fiber Reinforced Polymer Composites, Partha Pratim Das, Muthu Ram Prabhu Elenchezhian, Vamsee Vadlamudi, Rassel Raihan Jan 2023

Artificial Intelligence Assisted Residual Strength And Life Prediction Of Fiber Reinforced Polymer Composites, Partha Pratim Das, Muthu Ram Prabhu Elenchezhian, Vamsee Vadlamudi, Rassel Raihan

Institute of Predictive Performance Methodologies (IPPM-UTARI)

With the increased use of composite materials, researchers have developed many approaches for structural and prognostic health monitoring. Broadband Dielectric Spectroscopy (BbDS)/Impedance Spectroscopy (IS) is a state-of-the-art technology that can be used to identify and monitor the minute changes in damage initiation, accumulation, interactions, and the degree of damage in a composite under static and dynamic loading. This work presents a novel artificial neural network (ANN) framework for fiber-reinforced polymer (FRP) composites under fatigue loading, which incorporates dielectric state variables to predict the life (durability) and residual strength (damage tolerance) from real-time acquired dielectric permittivity of the material. The findings …


Hdd Dataset: Optimising Retrofitted Insulation For Irish Residential Building Walls, Rakshit D. Muddu, Aimee Byrne, Anthony James Robinson Jan 2023

Hdd Dataset: Optimising Retrofitted Insulation For Irish Residential Building Walls, Rakshit D. Muddu, Aimee Byrne, Anthony James Robinson

Datasets

In this study, a thermal-economic analysis was conducted to determine the optimum insulation thickness of retrofitted insulation walls in different regions in Ireland. This was based on the Heating Degree Day method (HDD). This dataset contains optimum insulation thickness, payback period, cost savings and carbon emission for all 25 counties in the Republic of Ireland


Dielectric Analysis To Predict Moisture Absorption In Structural Composites: A Data-Driven Approach, Partha Pratim Das, Monjur Morshed Rabby, Vamsee Vadlamudi, Rassel Raihan Jan 2022

Dielectric Analysis To Predict Moisture Absorption In Structural Composites: A Data-Driven Approach, Partha Pratim Das, Monjur Morshed Rabby, Vamsee Vadlamudi, Rassel Raihan

Institute of Predictive Performance Methodologies (IPPM-UTARI)

Due to continual exposure to moist environment, environmental degradation is a major threat to structural composites throughout their service life. Impedance Spectroscopy (IS)/Broadband Dielectric Spectroscopy (BbDS) is a reliable nondestructive method that has been used in polymer industries for dielectric characterization of material. While moisture absorption causes irreversible changes in the polymer matrix composites, it also alters the electrical properties of the system which is detectable using BbDS. Since the physics that drives the change in electrical characteristics is driven by the modifications imposed by water molecules (whether free or bound), both events can be linked. A dielectric spectrum over …


Moisture Content Prediction In Polymer Composites Using Machine Learning Techniques, Partha Pratim Das, Monjur Morshed Rabby, Vamsee Vadlamudi, Rassel Raihan Jan 2022

Moisture Content Prediction In Polymer Composites Using Machine Learning Techniques, Partha Pratim Das, Monjur Morshed Rabby, Vamsee Vadlamudi, Rassel Raihan

Institute of Predictive Performance Methodologies (IPPM-UTARI)

The principal objective of this study is to employ non-destructive broadband dielectric spectroscopy/impedance spectroscopy and machine learning techniques to estimate the moisture content in FRP composites under hygrothermal aging. Here, classification and regression machine learning models that can accurately predict the current moisture saturation state are developed using the frequency domain dielectric response of the composite, in conjunction with the time domain hygrothermal aging effect. First, to categorize the composites based on the present state of the absorbed moisture supervised classification learning models (i.e., quadratic discriminant analysis (QDA), support vector machine (SVM), and artificial neural network-based multilayer perceptron (MLP) classifier) …


The Effect Of Plasma Treatment On The Cure Behavior Of Out-Of-Life Prepregs And An Investigation Of The Mechanical Properties Of Composite Parts Manufactured From Plasma-Treated Prepregs, Monjur Morshed Rabby, Partha Pratim Das, Minhazur Rahman, Vamsee Vadlamudi, Rassel Raihan Jan 2022

The Effect Of Plasma Treatment On The Cure Behavior Of Out-Of-Life Prepregs And An Investigation Of The Mechanical Properties Of Composite Parts Manufactured From Plasma-Treated Prepregs, Monjur Morshed Rabby, Partha Pratim Das, Minhazur Rahman, Vamsee Vadlamudi, Rassel Raihan

Institute of Predictive Performance Methodologies (IPPM-UTARI)

Many industries, including aircraft, automobiles, and marine, are using prepreg (pre-impregnated fibers and a partially cured polymer matrix) to manufacture composite parts to achieve optimum fiber and resin volume ratio and part repeatability. Since prepregs have a short out oflife (i.e., the maximum storing time allowed at room temperature), they must be stored in refrigerators at low temperatures, which, if not maintained, have an unfavorable influence on the intended quality of the final product. For the present study, glass/epoxy prepregs (expired out-life) were plasmatreated before being used to make the composite part to compensate for the room temperature aging effect. …


Coupled Effects In Dielectric And Thermal Properties Of Polymer Matrix Composite Structures Due To Moisture Absorption, Partha Pratim Das, Monjur Morshed Rabby, Vamsee Vadlamudi, Kenneth Reifsnider, Rassel Raihan Jan 2022

Coupled Effects In Dielectric And Thermal Properties Of Polymer Matrix Composite Structures Due To Moisture Absorption, Partha Pratim Das, Monjur Morshed Rabby, Vamsee Vadlamudi, Kenneth Reifsnider, Rassel Raihan

Institute of Predictive Performance Methodologies (IPPM-UTARI)

Fiber reinforced polymer (FRP) composites are being used in number of fields including aerospace, marine, sports, medical, power sectors, etc. due to their lightweight nature while retaining high mechanical performance in terms of high specific strength, stiffness, and great fatigue properties. However, the applicability of these materials is restricted by their stability up to a certain temperature (i.e. glass transition temperature) and environmental degradation (i.e. moisture, UV light, etc.). Moisture ingression greatly reduces their mechanical properties altering material structure by causing polymer plasticization, chain scission and fiber-polymer interface deterioration. These changes instantaneously affect the thermal properties of the materials which …


Dielectric State Variables As Qualitative Indicators Of Moisture Absorption-Caused Mechanical Property Degradation In Gfrp Composite Structures, Partha Pratim Das, Vamsee Vadlamudi, Rassel Raihan Jan 2022

Dielectric State Variables As Qualitative Indicators Of Moisture Absorption-Caused Mechanical Property Degradation In Gfrp Composite Structures, Partha Pratim Das, Vamsee Vadlamudi, Rassel Raihan

Institute of Predictive Performance Methodologies (IPPM-UTARI)

Fiber reinforced polymer (FRP) composites are being used in numerous fields owing to their intrinsic strength to weight ratio and various design benefits. However, these materials are prone to environmental aging, particularly moisture absorption. In essence, absorbed moisture infiltrates the polymer matrix and induces changes in the polymer network through chain scission, plasticization, and other bonding interactions. This causes irreversible damages to the material and significantly decreases mechanical strength. In this study, Broadband Dielectric Spectroscopy (BbDS) has been used to identify the absorption mechanisms in glass fiber reinforced polymer (GFRP) composites by detecting the related polarization mechanisms. Here, results show …


Stiffness Degradation In Fatigue Life Of Composites Using Dielectric State Variables, Muthu Ram Prabhu Elenchezhian, Partha Pratim Das, Minhazur Rahman, Vamsee Vadlamudi, Rassel Raihan, Kenneth Reifsnider Oct 2021

Stiffness Degradation In Fatigue Life Of Composites Using Dielectric State Variables, Muthu Ram Prabhu Elenchezhian, Partha Pratim Das, Minhazur Rahman, Vamsee Vadlamudi, Rassel Raihan, Kenneth Reifsnider

Institute of Predictive Performance Methodologies (IPPM-UTARI)

Composite materials are widely used in aerospace and automotive structures for decades and over the years the community has gained a better understanding of the damage and failure modes of composites under fatigue. In this article, a dielectric characterization methodology for in-situ monitoring of composites under fatigue environments is proposed. A novel method of measuring the dielectric state variables in Broadband Dielectric Spectroscopy (BbDS) using Extremely Conductive Silver Epoxy Adhesive (ECSEA) paste is presented. These dielectric state variables serve to identify the precursor of the beginning of the end of life of the composite material under fatigue loading. The reliability …


The Effect Of Room-Temperature Aging On Enthalpy And Dielectric Property Of Carbon-Fiber/Epoxy Composite Prepreg And The Mechanical Property Of Manufactured Composite, Monjur Morshed Rabby, Minhazur Rahman, Partha Pratim Das, Muthu Ram Prabhu Elenchezhian, Relebohile George Qhobosheane, Vamsee Vadlamudi Jun 2021

The Effect Of Room-Temperature Aging On Enthalpy And Dielectric Property Of Carbon-Fiber/Epoxy Composite Prepreg And The Mechanical Property Of Manufactured Composite, Monjur Morshed Rabby, Minhazur Rahman, Partha Pratim Das, Muthu Ram Prabhu Elenchezhian, Relebohile George Qhobosheane, Vamsee Vadlamudi

Institute of Predictive Performance Methodologies (IPPM-UTARI)

Fiber-based reinforced plastics are widely used materials in different industries - e.g., Automotive, Aerospace, Defense- because of their various advantages. The most reliable raw materials for manufacturing fiber-based composites are pre-impregnated reinforcing fiber (prepreg). However, the limitation of using prepreg lies in its instability at room temperature. Prepregs have a specific out-life which sometimes makes the manufacturing process difficult. The objective of this study is to find out a way to investigate the room temperature aging effect on prepreg by analyzing the enthalpy and dielectric properties. In this study, differential scanning calorimetry (DSC) was used to measure the reaction enthalpy …


Supporting Materials From The Program "Development Of A Physically-Based Creep Model Incorporating Eta Phase Evolution For Nickel Base Superalloys", N. R. Mohale, C. L. White, P. G. Sanders, W. W. Milligan, J. P. Shingledecker, P. A. Bridges May 2021

Supporting Materials From The Program "Development Of A Physically-Based Creep Model Incorporating Eta Phase Evolution For Nickel Base Superalloys", N. R. Mohale, C. L. White, P. G. Sanders, W. W. Milligan, J. P. Shingledecker, P. A. Bridges

Michigan Tech Research Data

This research was funded by the US Department of Energy, Fossil Energy Program, Grant Number DE-FE0027822, with Omer Bakshi as the Program Manager. The grant conditions required that all supporting data and materials would be made publicly-available. This public repository was created on May 13, 2021.


Assessment Of Material State For Predicting The Durability Of Composites, Vamsee Vadlamudi, Muthu Ram Prabhu Elenchezhian, Partha Pratim Das, Rassel Raihan, Kenneth Reifsnider Sep 2020

Assessment Of Material State For Predicting The Durability Of Composites, Vamsee Vadlamudi, Muthu Ram Prabhu Elenchezhian, Partha Pratim Das, Rassel Raihan, Kenneth Reifsnider

Institute of Predictive Performance Methodologies (IPPM-UTARI)

The long term behavior of composites have been extensively studied for the last four decades. Given the heterogeneity of these materials, the damage accumulation mechanisms lead to superior fatigue performance of composites compared to metals. However, due to the ‘sudden death’ behavior controlled by defect coupling, the precursor to fracture plane development of these materials, the challenge remains on how to assess the real-time material state and predict when it becomes critical? In the recent past, broadband dielectric spectroscopy (BbDS) has been used successfully to assess the material state and predict the material state change (triggered by defect coupling) for …


Reduction Of Structural Damage From The Thermal Expansion Of Concrete Using Multifunctional Materials, Darren Hartl, Mirmilad Mirsayar Oct 2019

Reduction Of Structural Damage From The Thermal Expansion Of Concrete Using Multifunctional Materials, Darren Hartl, Mirmilad Mirsayar

Data

Corresponding data set for Tran-SET Project No. 18STTAM01. Abstract of the final report is stated below for reference:

"This study leveraged past successes in the analysis and design of shape memory alloy (SMA) components to address the issue of thermal expansion in concrete structures. Since the SMA used in the current work is relatively cheaper than other common SMAs (less than $50/lb compared to NiTi which is $200/lb due to difficulties in processing), it is anticipated that the findings of the study could be implemented in real infrastructures made of concrete, asphalt concrete, and other complex large infrastructure. Low-cost Fe-SMAs …


Soil-Recycled Aggregate-Geopolymer Road Base/Subbase Mixtures: Steps Towards Sustainability, Mohammad Khattak, Daniel Odion Oct 2019

Soil-Recycled Aggregate-Geopolymer Road Base/Subbase Mixtures: Steps Towards Sustainability, Mohammad Khattak, Daniel Odion

Data

Corresponding data set for Tran-SET Project No. 18GTLSU10. Abstract of the final report is stated below for reference:

"This study deals with the development of Soil-Geopolymer mixtures using flyash, alkali activator and recycled aggregates (RAG) including recycled concrete (RCA) and reclaimed asphalt (RAP) as an alternative to soil-cement for pavement base and subbase layers. Several mix constituents were varied such as flyash type and content, RCA and RAP content and ratio of sodium silicate and sodium hydroxide. Experiment design was established and mechanical and durability characteristics of Soil-RAG-Geopolymer mixtures were evaluated and then compared to the conventional soil-cement mixtures. The …


Development Of Geopolymer-Based Cement And Soil Stabilizers For Transportation Infrastructure, Miladin Radovic, Anand Puppala Sep 2019

Development Of Geopolymer-Based Cement And Soil Stabilizers For Transportation Infrastructure, Miladin Radovic, Anand Puppala

Data

Corresponding data set for Tran-SET Project No. 18CTAM03. Abstract of the final report is stated below for reference:

"Geopolymer Cement (GPC) has drawn much attention in the recent years as an alternative to Ordinary Portland Cement (OPC) for soil stabilization, pavements, bridges and other transportation structures due to their good mechanical properties in comparison to OPC. In addition, GPC can be processed at room temperatures from aqueous solutions of waste materials (e.g. fly ash) or abundant natural sources (e.g. clay), thereby significantly reducing CO2 production associated with processing of OPC. As such, GPC proves to be a more sustainable and …


Mitigating Reflective Cracking Through The Use Of A Ductile Concrete Interlayer, Qian Zhang, Mohammad Khattak, Adway Das Sep 2019

Mitigating Reflective Cracking Through The Use Of A Ductile Concrete Interlayer, Qian Zhang, Mohammad Khattak, Adway Das

Data

Corresponding data set for Tran-SET Project No. 18PLSU13. Abstract of the final report is stated below for reference:

"Reflective cracking is considered one of the most important issues that causes premature deterioration of composite pavements. Many types of mitigation methods have been studied in the past. However, they are either not effective in delaying the reflective cracking, or they only extend the service life by a few years. To address this critical issue and significantly extend the service life of the composite pavement, in this research, a ductile interlayer made of engineered cementitious composites (ECC) was proposed. It was hypothesized …


Toward Non-Corrosion And Highly Sustainable Structural Members By Using Ultra-High-Performance Materials For Transportation Infrastructure, Shih-Ho Chao, Ashish Karmacharya Sep 2019

Toward Non-Corrosion And Highly Sustainable Structural Members By Using Ultra-High-Performance Materials For Transportation Infrastructure, Shih-Ho Chao, Ashish Karmacharya

Data

Corresponding data set for Tran-SET Project No. 18STUTA01. Abstract of the final report is stated below for reference:

"This research focused on investigating a highly sustainable and efficient reinforced concrete structural member for future infrastructure by utilizing emerging high-performance materials. These materials include ultra-high-performance fiber-reinforced concrete (UHP-FRC) and corrosion-resistant high-strength fiber-reinforced polymer (FRP) bars. Four reduced scale UHP-FRC specimens were tested under large displacement reversals to prove the proposed new ductile-concrete strong-reinforcement (DCSR) design concept by fully utilizing these ultra-high-performance materials. Micro steel fibers were incorporated into three specimens and ultra-high molecular weight polyethylene fibers were blended into the fourth …


Use Of Rice Husk Ash (Rha) In Flowable Fill Concrete Mix Material, Zahid Hossain, Kazi Tamzidul Islam Aug 2019

Use Of Rice Husk Ash (Rha) In Flowable Fill Concrete Mix Material, Zahid Hossain, Kazi Tamzidul Islam

Data

Corresponding data set for Tran-SET Project No. 18CASU03. Abstract of the final report is stated below for reference:

"In the way of finding sustainable development, the flowable fill is a relatively new construction technology. Flowable fill is a self-compacting material, which has been developed in recent years. Flowable fill has been used for different applications such as backfilling walls, sewer trenches, bridge abutments, conduit trenches, pile excavations, and retaining walls. This study examines the potential uses of Rice Husk Ash (RHA) as a sustainable cementitious material (SCM) in the preparation of flowable fill concrete. (RHA is an agricultural by-product of …


Self-Healing Concrete Using Encapsulated Bacterial Spores In A Simulated Hot Subtropical Climate, Marwa Hassan, Jose Milla, Tyson Rupnow, Ahsennur Soysal Aug 2019

Self-Healing Concrete Using Encapsulated Bacterial Spores In A Simulated Hot Subtropical Climate, Marwa Hassan, Jose Milla, Tyson Rupnow, Ahsennur Soysal

Data

Corresponding data set for Tran-SET Project No. 18CLSU02. Abstract of the final report is stated below for reference:

"Bacterial concrete has become one of the most promising self-healing alternatives due to its capability to seal crack widths through microbial induced calcite precipitation (MICP). In this study, two bacterial strains were embedded at varying dosages (by weight of cement) in concrete. Beam specimens were used to identify the maximum crack-sealing efficiency, while cylinder samples were used to determine their effects on the intrinsic mechanical properties, as well as its stiffness recovery over time after inducing damage. The concrete specimens were cured …


Use Of Bagasse Ash As A Concrete Additive For Road Pavement Application, Gabriel Arce, Marwa Hassan, Maria Gutierrez-Wing, Michele Barbato Aug 2019

Use Of Bagasse Ash As A Concrete Additive For Road Pavement Application, Gabriel Arce, Marwa Hassan, Maria Gutierrez-Wing, Michele Barbato

Data

Corresponding data set for Tran-SET Project No. 18CLSU03. Abstract of the final report is stated below for reference:

"The objective of this study was to evaluate the use of sugarcane bagasse ash (SCBA) as a partial replacement of cement in concrete for road pavement application. The study explored the pozzolanic activity of SCBA produced from three different processing methodologies (i.e., raw SCBA, controlled SCBA and post-processed SCBA). The experimental results revealed that SCBA produced by the controlled burning of sugarcane bagasse fiber (SBF) at 650°C and grinding (C-650), presented the maximum pozzolanic activity. However, this SCBA production process was deemed …


Uhpc Shear Keys In Concrete Bridge Superstructures, Craig Newtson, Brad Weldon, Elsy Flores, Jordan Varbel, William Toledo Aug 2019

Uhpc Shear Keys In Concrete Bridge Superstructures, Craig Newtson, Brad Weldon, Elsy Flores, Jordan Varbel, William Toledo

Data

Corresponding data set for Tran-SET Project No. 18CNMS01. Abstract of the final report is stated below for reference:

"This research investigated the use of locally produced ultra-high performance concrete (UHPC) as a grouting material to repair deteriorated shear keys. Shear keys are used in adjacent girder superstructures to produce monolithic behavior and load transfer across the structure. Shear key durability is a concern since shear key degradation can jeopardize the integrity of the structure. Transportation agencies have reported that 75% of distress in adjacent girder bridges is due to cracking and de-bonding along shear keys. Previous research has shown that …


Elimination Of Empirical, Ineffective And Expensive Pg Plus Tests To Characterize Modified Binders, Zahid Hossain, Ashraf Elsayed, Mm Tariq Morshed, Mohammad Hassan Aug 2019

Elimination Of Empirical, Ineffective And Expensive Pg Plus Tests To Characterize Modified Binders, Zahid Hossain, Ashraf Elsayed, Mm Tariq Morshed, Mohammad Hassan

Data

Corresponding data set for Tran-SET Project No. 18BASU02. Abstract of the final report is stated below for reference:

"For characterizing the polymer modified binders, different state Departments of Transportation (DOTs) use different time consuming and empirical Performance Grade (PG) Plus test methods. Furthermore, the PG Plus tests are silent when asphalt binders are modified with chemicals such as polyphosphoric acid (PPA). But, the effects of the elastomeric or plastomeric polymer are not accurately identified through these conventional tests such as Elastic Recovery (ER) and tenacity. Thus, the main research goal of this study is to recommend alternative test method(s), which …


Disaster Resilient And Self-Assessing Multifunctional Transportation Structures, Ibrahim Karaman, Darren Hartl Aug 2019

Disaster Resilient And Self-Assessing Multifunctional Transportation Structures, Ibrahim Karaman, Darren Hartl

Data

Corresponding data set for Tran-SET Project No. 18STTAM02. Abstract of the final report is stated below for reference:

"This research designs and characterizes multifunctional materials, in particular inexpensive shape memory alloys, for transportation structures that possess excellent mechanical properties and self-sensing capabilities for strengthening and health monitoring. The properties are the Fe-SMAs are sensitive to part size in that the grain size of the material, which can be grown to several inches, should exceed the smallest dimension of the part. In the current work, maximum part size of the large dimension Fe-SMA rods were determined through detailed microstructural investigations. Samples …


Characteristics Of Bi-Metallic Interfaces Formed During Direct Energy Deposition Additive Manufacturing Processing, Ryan Anderson, Jordan Terrel, Judy Schneider, Sean Thompson, Paul Gradl May 2019

Characteristics Of Bi-Metallic Interfaces Formed During Direct Energy Deposition Additive Manufacturing Processing, Ryan Anderson, Jordan Terrel, Judy Schneider, Sean Thompson, Paul Gradl

PRC-Affiliated Research

Various additive manufacturing processes are being evaluated to reduce the time and cost for fabrication of low volume, complex, and multifunctional assemblies. This study evaluated two direct energy deposition processes for the fabrication of large bi-metallic structures. The materials evaluated were Inconel 625 and copper alloy C18150, which are used in various high heat flux applications. Inconel was deposited onto the C18150 substrate using blown powder and wire-fed processes. Complete bonding was obtained in both processes and the resulting interfaces were evaluated using microscopy and indentation testing. Differences were observed in the interface region suggesting the kinetic energy of the …


Characteristics Of Bi-Metallic Interfaces Formed During Direct Energy Deposition Additive Manufacturing Processing, Ryan Anderson, Jordan Terrel, Judy Schneider, Sean Thompson, Paul Gradl May 2019

Characteristics Of Bi-Metallic Interfaces Formed During Direct Energy Deposition Additive Manufacturing Processing, Ryan Anderson, Jordan Terrel, Judy Schneider, Sean Thompson, Paul Gradl

PRC-Affiliated Research

Various additive manufacturing processes are being evaluated to reduce the time and cost for fabrication of low volume, complex, and multifunctional assemblies. This study evaluated two direct energy deposition processes for the fabrication of large bi-metallic structures. The materials evaluated were Inconel 625 and copper alloy C18150, which are used in various high heat flux applications. Inconel was deposited onto the C18150 substrate using blown powder and wire-fed processes. Complete bonding was obtained in both processes and the resulting interfaces were evaluated using microscopy and indentation testing. Differences were observed in the interface region suggesting the kinetic energy of the …


Characteristics Of Bi-Metallic Interfaces Formed During Direct Energy Deposition Additive Manufacturing Processing, Ryan Anderson, Jordan Terrel, Judy Schneider, Sean Thompson, Paul Gradl May 2019

Characteristics Of Bi-Metallic Interfaces Formed During Direct Energy Deposition Additive Manufacturing Processing, Ryan Anderson, Jordan Terrel, Judy Schneider, Sean Thompson, Paul Gradl

PRC-Affiliated Research

Various additive manufacturing processes are being evaluated to reduce the time and cost for fabrication of low volume, complex, and multifunctional assemblies. This study evaluated two direct energy deposition processes for the fabrication of large bi-metallic structures. The materials evaluated were Inconel 625 and copper alloy C18150, which are used in various high heat flux applications. Inconel was deposited onto the C18150 substrate using blown powder and wire-fed processes. Complete bonding was obtained in both processes and the resulting interfaces were evaluated using microscopy and indentation testing. Differences were observed in the interface region suggesting the kinetic energy of the …


Study Of Synthesis Of Biodegradable Plastics From Alkaline Fermented Excessive Activated Sludge, Yaohui Liu, Chua Hong Jan 2019

Study Of Synthesis Of Biodegradable Plastics From Alkaline Fermented Excessive Activated Sludge, Yaohui Liu, Chua Hong

Faculty of Science & Technology (THEi)

The environmental problems associated with plastics have become increasingly severe in recent years. Technologically and economically feasible solutions are in urgent need in order to ensure sustainable development in the plastic industry. Polyhydroxyalkanoates (PHAs) are a family of specialized polyesters of hydroxyalkanoates (HAs) and can be completely degraded in natural environment. They can be synthesized naturally or under artificially controlled processes. The barrier of limiting the application of PHAs is the high production cost. From years of study, PHAs are proofed to be able to be accumulated within the bacterial cells in activated sludge and the production yield had been …


An Orthogonal Study Of Industrial Scale Colour Fading Process Of Cotton Fabric, Yaohui Liu, Chester Kin-Man To, Hiu-Yan Cheung, Chi-Wai Kan, Chua Hong Jan 2019

An Orthogonal Study Of Industrial Scale Colour Fading Process Of Cotton Fabric, Yaohui Liu, Chester Kin-Man To, Hiu-Yan Cheung, Chi-Wai Kan, Chua Hong

Faculty of Science & Technology (THEi)

Colour fading is now a popular process used for imparting a vintage look to textile and fashion products, which enhances market value because of the current fashion trends. This study examined a non-aqueous colour fading process with the use of oxygen plasma-induced ozone treatment. An industrial scale machine and commercially available red sulpur-dyed cotton fabric (with 0.5 %, 1.5 % and 2.5 % colour depths) were used in this study. Since the colour fading process factors are inter-related to each other, a specific experiment approach, i.e. orthogonal method, was used for obtaining the optimum conditions in an industrial scale colour …


Atmospheric Pressure Plasma‐Induced Decolorisation Of Cotton Knitted Fabric Dyed With Reactive Dye, Yaohui Liu, Chester Kin-Man To, Mei‐Ki Ngai, Chi-Wai Kan, Chua Hong Jan 2019

Atmospheric Pressure Plasma‐Induced Decolorisation Of Cotton Knitted Fabric Dyed With Reactive Dye, Yaohui Liu, Chester Kin-Man To, Mei‐Ki Ngai, Chi-Wai Kan, Chua Hong

Faculty of Science & Technology (THEi)

The aim of this study was to investigate the decolorisation effect of atmospheric pressure plasma treatment on knitted fabrics dyed with reactive dyes under different processing parameters, ie, air concentration, treatment duration and water content. The fabrics were dyed with reactive dye of a blue colour, and the colour depths were 0.5%, 1.5% and 3.0% on weight of fabric. The colour properties of untreated and plasma‐treated fabric samples were evaluated by means of reflectance, K/S and relative unlevelness index. The colour properties were evaluated instrumentally and quantitatively in order to study the decolorisation effect induced by atmospheric pressure plasma treatment. …


Enhancing The Durability And The Service Life Of Asphalt Pavements Through Innovative Light-Induced Self-Healing Materials, Marwa Hassan Dec 2018

Enhancing The Durability And The Service Life Of Asphalt Pavements Through Innovative Light-Induced Self-Healing Materials, Marwa Hassan

Data

Corresponding data set for Tran-SET Project No. 17BLSU02. Abstract of the final report is stated below for reference:

"The objective of this study was to evaluate the efficiency of a new generation of Ultraviolet (UV) light-induced self-healing polymers in enhancing the durability and self-healing properties of asphalt mixtures. Self-healing polymers were successfully synthesized in the laboratory and were characterized using Fourier Transform Infrared Spectroscopy (FTIR). In addition, Thermogravimetric Analysis (TGA) results showed that the synthesized polymers achieved the required thermal stability to resist asphalt mixture production processes. Viscosity results showed that addition of 5% Recycled Asphalt Shingle (RAS) and/or 20% …