bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantum Machine Learning: The Superhero That Classical Machine Learning Never Knew It Needed
Authors: Roy Mahule
Published: October 2024

Quantum Machine Learning (QML) is an emerging interdisciplinary field that combines the principles of quantum mechanics and machine learning to develop algorithms that can potentially outperform classical algorithms in certain tasks. QML leverages the unique properties of quantum systems, such as superposition and entanglement, to process information in ways that are not possible with classical computers. This paper provides a comprehensive overview of QML, including its principles, algorithms, and applications. We focus particularly on supervised learning methods, which involve training a quantum model on labeled data to make predictions on new, unseen data. We discuss the potential of QML to revolutionize various domains, such as finance, chemistry, and materials science, and highlight the challenges associated with the development and implementation of QML algorithms, including the need for more advanced quantum hardware and software. This paper aims to provide a clear understanding of the current state of QML research and its potential impact on future computational capabilities.
Uroczystości, stroje i insygnia w ceremoniale Uniwersytetu Warszawskiego 1816–1939
Authors:   University of Warsaw, Tyszkiewicz Adam
Published: October 2024

The book is devoted to the customs of the University of Warsaw from its establishment in 1816 until the 20th century. It is the first monograph of this type concerning celebrations and ceremonial paraphernalia of the University. The author shows the role that academic rites played in many spheres of functioning of the University. He supplements his work with reproductions of archival photographs and documents, and numerous colour illustrations presenting the rich world of the university ceremonial. The starting point for the author’s considerations were the traditions of European research centres, such as Bologna, Paris, London and Berlin, as well as the oldest Polish universities in Cracow, Vilnius and Lviv.
Characterization of Build Parameters and Microstructure in Low Heat Input Wire-Arc Additive Manufacturing of Ni-based Superalloy Haynes 282
Authors: Adam Benjamin , Turpin Robert , Tewksbury Graham , Feng Rui , Sudbrack Chantal , Pohl Mathias , Jarvis Karl , Crandall Dustin
Published: October 2024

Ni-based superalloy Haynes 282 is a prime candidate for advanced power generation systems due to its superior fabricability, weldability, and high-temperature performance. Additive manufacturing offers potential cost and time savings for gas turbine components. Wire-arc direct energy deposition can create large components but often requires post-processing treatments, such as hot isostatic pressing (HIP), to address porosity. This study explores a low heat-input, high deposition rate GMAW process to achieve fully dense Haynes 282 without HIP. Twenty-one blocks were deposited, varying travel and wire feed speeds. Initial analysis (visual inspection, microstructural examination, and CT) revealed the impact of build parameters on internal porosity and defects. Scanning electron microscopy provided insights into structural heterogeneity and microstructural properties.
Development and Commercialization of Adaptive Feedback Welding Technology for Fabrication and Repair Applications
Authors: Belhout Shems-Eddine , Tatman Jon , Barborak Darren , Hargadine Mitch , von Querfurth Benedikt , Knaak Christian , Mann Stefan , Bialach Janusz , Clemence Dana , Wright Michael
Published: October 2024

There is a growing need to automate the gas tungsten arc welding process for fabrication and repair of nuclear components due to an increasing shortage of experienced welders. Therefore, a collaborative effort has been performed in this study to develop a fully autonomous gas tungsten arc welding system with adaptive capabilities. The system employs the application of two neural networks that have been presented in. The first utilizes a vision based convolutional neural network to perform real time control of the filler wire entry position into the weld pool. The second predicts optimal weld parameters and torch positioning for each weld pass deposited within a multi-pass groove. A commercialization path for the technology is in-progress, with the artificial intelligent algorithms currently being incorporated and tested on commercially available equipment.
Evaluation of the Mechanical Properties of Cast and Wrought CF8C-Plus Relevant to ASME Code Case Qualification
Authors: Chen Xiang (Frank) , Tortorelli Peter F. , Santella Michael L. , Pint Bruce A. , Wang Hong , Maziasz Philip J. , Sutton Benjamin , Purdy Daniel
Published: October 2024

The mechanical behavior of a cast form of an advanced austenitic stainless steel, CF8C-Plus, is compared with that of its wrought equivalent in terms of both tensile and creep-rupture properties and estimated allowable stress values for pressurized service at temperatures up to about 850°C. A traditional Larson-Miller parametric model is used to analyze the creep-rupture data and to predict long-term lifetimes for comparison of the two alloy types. The cast CF8C-Plus exhibited lower yield and tensile strengths, but higher creep strength compared to its wrought counterpart. Two welding methods, shielded-metal-arc welding (SMAW) and gas-metal-arc welding, met the weld qualification acceptance criteria in ASME BPVC Section IX for the cast CF8C-Plus. However, for the wrought CF8C-Plus, while SMAW and gas-tungsten-arc welding passed the tensile acceptance criteria, they failed the side bend tests due to lack of fusion or weld metal discontinuities.
Complex Linear Welding Development for Thick Section Electron Beam Welding for Pressure Vessel Applications
Authors: Dutilleul Thomas , Widdison Robert , Connell James , Crossley John , Albert Mark , Gandy David
Published: October 2024

As part of a Department of Energy (DOE) funded program assessing advanced manufacturing techniques for Small Modular Reactor (SMR) applications, the Nuclear Advanced Manufacturing Research Centre (AMRC) and the Electric Power Research Institute (EPRI) have been developing Electron Beam Welding (EBW) parameters and procedures based upon SA508 Grade 3 Class 1 base material. The transition shell, a complex component connecting the lower assembly to the upper assembly is a shell that flares up with varying thicknesses across its section. The component due to its geometry could be built by near net shape powder metallurgy hot isostatic pressing instead of conventional forging techniques. The demonstrator transition shell here is built from several sub-forging as a training exercise. The complex geometry and joint configuration were selected to assess the EBW as a suitable technique. This paper presents results from the steady state welding in the 60-110 mm material thickness range, showing that weld properties meet specification requirements. Weld quality was assured by Time-of-Flight Diffraction (ToFD). The transition shell was completed by welding a flange to the assembly. The presented transition shell assembly represents 6 welded sections all fabricated in below 100 min total welding time.
Fiber-jacketed Creep Resistant Pipes for High-Temperature Applications
Authors: Friedrich Maximilian , Klenk Andreas , Weihe Stefan
Published: October 2024

In order to enable safe long-term operation, metallic pipes operated in the creep range at high temperatures require considerable wall thicknesses at significant operating pressures, such as those required in thermal power plants of all kinds or in the chemical industry. This paper presents a concept that makes it possible to design such pipes with thinner wall thicknesses. This is achieved by adding a jacket made of a ceramic matrix composite material to the pipe. The high creep resistance of the jacket makes it possible to considerably extend the service life of thin- walled pipes in the creep range. This is demonstrated in the present paper using hollow cylinder specimens. These specimens are not only investigated experimentally but also numerically and are further analyzed after failure. The investigations of the specimen show that the modeling approaches taken are feasible to describe the long-term behavior of the specimen sufficiently. Furthermore, the paper also demonstrates the possibility of applying the concept to pipeline components of real size in a power plant and shows that the used modeling approaches are also feasible to describe their long-term behavior.
Tensile Property Measurement of AlSi10Mg Lattice Structures - From Single Strut to Lattice Networks
Authors: Fry A.T , Crocker L. E. , Woolliams P. , Poole M. , Koko A. , Breheny C.
Published: October 2024

At present there is no recognized standard test method that can be used for the measurement of the tensile properties of additively manufactured lattice structures. The aim of this work was to develop and validate a methodology that would enable this material property to be measured for these geometrically and microstructurally complex material structures. A novel test piece has been designed and trialed to enable lattice struts and substructures to be manufactured and tested in standard bench top universal testing machines and in small scale in-situ SEM loading jigs (not reported in this paper). In conjunction with the mechanical tests, a finite element (FEA) modelling approach has been used to help cross validate the methodology and results, and to enable larger lattice structures to be modelled with confidence. The specimen design and testing approach developed, is described and the results reviewed for AlSi10Mg.
Use of Modeling and Experiments to Assess the Effect of Minor Alloying Additions on Alumina Scale Formation during High-Temperature Oxidation
Authors: De Vecchis Rafael Rodríguez , Gleeson Brian , Pillai Rishi
Published: October 2024

During the last decades, new generations of Ni-based superalloys have emerged with judiciously controlled chemistries. These alloys heavily rely on the addition of refractory elements to enhance their mechanical properties at elevated temperatures; however, a clear interpretation of the influence of these minor-element additions on the alloy's high-temperature oxidation behavior is still not well understood, particularly from the standpoint of predicting the transition from internal to external alumina formation. In this context, the present investigation describes a systematic study that addresses the intrinsic effects that minor element additions of Nb, Ta, and Re have on the oxidation behavior of alumina-scale forming γ-Ni alloys. By combining a novel simulation approach with high-temperature oxidation experiments, the present study evidences the generally positive effect associated with 2 at. % addition of Ta and Re as well as the detrimental consequences of Nb additions on the 1100 °C oxidation of (in at. %) Ni-6Al-(0,4,6,8)Cr alloys.
Evaluation of Highly Irradiated Stainless Steel and Nickel-based Materials using Phased Array Ultrasonic Inspections
Authors: Johnson Kristian C. , MacLauchlan Daniel T. , Phan H. Josiah , Wiggins B. Blake , Williams Cody D. , Tatman Jonathan
Published: October 2024

Nuclear reactor inspections occasionally identify degraded materials in irradiated reactor components. Although mechanical repair options are possible, these repair solutions may be cost prohibitive or impractical to implement due to access restraints and/or the severity of the degradation. Welding repair of reactor components may input excessive heat into these irradiated materials resulting in diffusion of trace amounts of helium within the grain boundaries of the weld heat-affected zone (HAZ). Intergranular HAZ cracking can then result from the combination of this helium diffusion and high localized tensile stresses generated during weld cooling. It is therefore critical to characterize these zones and understand limitations for welding highly irradiated components to prevent helium-induced cracking. To accomplish this, typical reactor structural materials including Types 304L and 316L stainless steels and nickel-based Alloy 600/182 materials irradiated within the High Flux Isotope Reactor facility at Oak Ridge National Laboratory were used in this study for welding and evaluation. A phased array ultrasonic inspection system has been developed to characterize cracking in the weld samples. It provides remote controlled scanning and minimizes handling the samples, minimizing operator dose. The samples are inspected from the side opposite of the welds. The material and weld grain noise were evaluated at 10 MHz and found to be conducive to detecting cracking in the material and welds. Inspection of the samples comprises a 10 MHz phased array probe sweeping a focused longitudinal wave from -60° to 60° while the probe is raster scanned over the sample in small increments. The collected data is analyzed using UltraVision 3. Several of the irradiated samples were inspected prior to welding. Some of the samples had what appear to be small lamination defects in them. One irradiated welded sample has been tested to date with no cracking detected, which has been confirmed by destructive examination.
Atmosphere Influence on the Fatigue Crack Growth Behavior of Wrought, Cast and PBF-LB/M Processed IN718 under Different Loading Conditions at 650 °C
Authors: Brune T. , Kraemer K. M. , Kontermann C. , Oechsner M. , Bellmer M. , Schlesinger M.
Published: October 2024

For the safe life prediction of components under high cycle fatigue loading at high temperature, such as gas turbine blades and turbocharger components, the behavior of initial defects, which are physically short cracks below the long crack threshold ΔK is of crucial importance. The evolution of different crack closure mechanisms (such as plasticity, roughness and oxide induced crack closure) can lead to crack arrest by a reduction of the effective crack tip loading. To visualize the crack growth behavior of such cracks, cyclic crack resistance curves (cyclic R-curves) are used. The experimental determination of cyclic R-curves is challenging, especially under high temperature conditions due to a lack of optical accessibility. The formation of very short cracks in high strength materials makes it even more complicated to reliably determine these data. Within this study the crack growth behavior of physically short fatigue cracks in three different material states of the nickel alloy IN718 (wrought, cast and PBF-LB/M - processed) is experimentally determined at 650 °C. Based on a load increase procedure applied on Single Edge Notched (SEN) specimens with a compression pre-cracking procedure in advance, crack propagation of physically short cracks is measured with alternating current potential drop systems in air and under vacuum conditions. These examinations are carried out for three different load ratios (R = -1, 0 and 0.5) to investigate the amount of certain crack closure mechanisms active under different loading conditions. Moreover, the formation of a plastic wake along the crack flanks is determined by a finite element simulation. The results determined in air and under vacuum conditions are used to describe the impact of oxide induced crack closure on the behavior of physically short cracks. This allows the evaluation of the behavior of both near-surface and internal defects that are not accessible to the atmosphere.
Damage of Rankine Cycle Components in Concentrated Solar Power Plants
Authors: Kung Steven , Caravaggio Michael
Published: October 2024

The steam generation systems (SGS) of concentrated solar power (CSP) plants employ multiple heat exchangers arranged in series to convert thermal energy collected from the sun via a heat transfer fluid (HTF) to produce superheated steam in the Rankine cycle. Common CSP plant designs are based either on parabolic trough or central tower technology. The major Rankine cycle components consist of preheaters, evaporators, steam drums, superheaters, steam turbines, and water/air-cooled condensers, all connected through steel piping. For CSP plants capable of reheating the steam for improved efficiency, reheaters are also included in the Rankine cycle. In central tower design with directly heated water as the HTF, the receiver can also be considered part of the Rankine cycle. Operating experiences of CSP plants indicate that plant reliability is significantly impacted by failures in various components of the Rankine cycle. Many damage mechanisms have been identified, which include corrosion, thermal fatigue, creep, and stress corrosion cracking, among others. Much of the damage can be attributed to poor water/steam chemistry and inadequate temperature control. While damage in the Rankine cycle components is common, there is generally lack of comprehensive guidelines created specifically for the operation of these CSP components. Therefore, to improve CSP plant reliability and profitability, it is necessary to better understand the various damage mechanisms experienced by linking them to specific operating conditions, followed by developing a “theory and practice” guideline document for the CSP operators, so that failures in the Rankine cycle components can be minimized. In a major research project sponsored by the U.S. Department of Energy (DOE), effort is being undertaken by EPRI to develop such a guideline document exclusively for the CSP industry. This paper provides an overview of the ongoing DOE project along with a few examples of component failures experienced in the Rankine cycle.
Analysis of Crystal Structure in Temper Embrittled 12% Cr Turbine Blade Steel
Authors: Lee Gil Jae , Choe Byung Hak
Published: October 2024

This study investigates the mechanisms of temper embrittlement in 410 martensitic stainless steel, a material widely used in steam turbine blades due to its excellent corrosion resistance and high strength achieved through quenching and tempering heat treatments. While the material’s hardness and impact toughness strongly depend on tempering temperatures, significant embrittlement occurs around 540°C, manifesting as decreased Charpy impact energy alongside increased strength and hardness. To understand this phenomenon at the nanometer scale, high-resolution transmission electron microscopy (TEM) analysis was performed, focusing on electron diffraction patterns along the <110>α-Fe and <113>α-Fe zone axes. The analysis revealed distinctive double electron diffraction spots at 1/3(211) and 2/3(211) positions, with lattice spacing of approximately 3.5 Å—triple the typical α-bcc lattice spacing (1.17 Å). These regions were identified as metastable “zones” resembling ω-phase structures, potentially responsible for the embrittlement. While this newly identified phase structure may not fully explain the complex mechanisms of temper embrittlement, it provides valuable insights for developing improved alloying and heat treatment methods to mitigate embrittlement in martensitic steels.
High-Performance Corrosion and Erosion Resistance of an Amorphous Iron-Based Alloy Coating Exposed to Molten FLiNaK Salt Nuclear Reactor Coolant at 700 °C
Authors: Maya-Visuet Enrique
Published: October 2024

This presentation compares the corrosion resistance of uncoated Haynes 230 and SS316HS substrates to the same substrates coated with a Fe-based amorphous alloy. The substrates were exposed to highly corrosive media, FLiNaK, for 120 hours at 700 °C. The findings indicate that the thermal spray amorphous alloy coating provided superior corrosion resistance within the coatings while protecting the substrates against the aggressive environment. As a result, the new amorphous metal coating improved the substrate's lifespan by providing better protection against high-temperature corrosion, paving the way for a more efficient and cost-effective future in various industrial applications.
Friction Stir Layer Deposition of a High Entropy Alloy for Nuclear Applications
Authors: Meher Subhashish , Garcia David , Nartu Mohan S.K.K.Y. , Wang Tianhao , Irving  , Brown  , dos Santos Jorge F. , van Rooyen Isabella
Published: October 2024

Friction Stir Layer Deposition on a Cu-containing high-entropy alloy (HEA) has been performed for its suitability of the core component of nuclear materials. Excellent irradiation resistance in this Cu-containing HEA has been reported previously. Friction stir layer deposition (FSLD) offers a solid-state deformation processing route to metal additive manufacturing, in which the feed material undergoes severe plastic deformation at elevated temperatures. Some of the key advantages of this process are fabrication of fully dense material with fine, equiaxed grain structures. This work reports the detailed microstructure of the FSLD product, and it discusses the grain refinement and micro-hardness variation observed in FSLD product.
Weldability Evaluation of Computationally Designed Filler Wires for Wire-Arc Additive Manufacturing of Functionally Graded Materials in Harsh Service Environments
Authors: Melaragno Giacomo , Alexandrov Boian , Shingledecker John , Siefert John , Gagliano Michael , Penso Jorge
Published: October 2024

Olefin furnaces contain gravity cast U-bend fittings from Fe-Ni-Cr alloys that can experience premature failures due to a combination of harsh service conditions. The fittings undergo steep temperature variations during startup and shutdown, outer diameter (OD) oxidation from furnace flue gases, and inner diameter (ID) carburization from process fluids. As a result, cracking often occurs along large solidification grain boundaries from interconnected networks of carbides and secondary phases. To address these degradation concerns, Wire Arc Additive Manufacturing (WAAM) is being used to produce a functionally graded fitting that provides increased oxidation, carburization, creep, and thermal fatigue resistance. Three welding wire compositions have been designed based on thermodynamic and kinetic modeling techniques to address the appropriate corrosion resistance and mechanical properties needed in the OD, Core, and ID regions of the U- bend fitting cross-section. A Fe-35Cr-45Ni-0.7Nb solid welding wire is being used for the Core section, and metal-cored welding wires based around this composition with additions of Si or Al are being used for the OD and ID sections, respectively. This study involved weldability evaluation focused on understanding the microstructures and potential additive manufacturing printability challenges associated with graded WAAM structures using these welding wires. To achieve this, Cast Pin Tear Testing (CPTT) was performed to evaluate solidification cracking susceptibility of the welding wires. Additionally, Scheil calculations were performed in Thermo-Calc software to predict solidification microstructures. To validate the results, SEM characterization was conducted on cast buttons of each welding wire to identify phases in the respective microstructures. These unique data will help inform WAAM design parameters needed to produce a Functionally Graded Material (FGM) that improves the lifetime of Fe-Ni-Cr U-bend fittings in olefin furnaces.?
ABD-1000AM: a Highly Processible Superalloy for Additive Manufacturing, Computationally Designed for 1000°C Applications
Authors: Peachey Dominic , He Yining , Zhang Pimin , Clark John , Hussain Zara , Wagstaff Thomas , Nemeth André , Crudden David
Published: October 2024

The advancement of additive manufacturing (AM) technology has heightened interest in producing components from nickel-based superalloys for high-temperature applications; however, developing high gamma prime (γ’) strengthened alloys suitable for AM at temperatures of 1000°C or higher poses significant challenges due to their “non-weldable” nature. Traditional compositions intended for casting or wrought processes are often unsuitable for AM due to their rapid heating and cooling cycles, leading to performance compromises. This study introduces ABD-1000AM, a novel high gamma prime Ni-based superalloy designed using the Alloys-by-Design computational approach to excel in AM applications at elevated temperatures. Tailored for AM, particularly powder bed fusion, ABD-1000AM demonstrates exceptional processing capability and high-temperature mechanical and environmental performance at 1000°C. The study discusses the alloy design approach, highlighting the optimization of key performance parameters, composition, and process-microstructure-performance relationships to achieve ABD-1000AM’s unique combination of processability and creep resistance. Insights from ABD-1000AM’s development inform future directions for superalloy development in complex AM components.
Creep Ductility in 9Cr Creep Strength Enhanced Ferritic Steels - Part II, Microstructural Observations
Authors: Siefert John A. , Parker Jonathan D. , Perrin Ian J.
Published: October 2024

The time-dependent behavior of 9Cr creep strength enhanced ferritic (CSEF) steels has long fixated on the creep life recorded in uniaxial constant load creep tests. This focus is a consequence of the need to develop stress allowable values for use in the design by formulae approach of rules for new construction. The use of these simple rules is justified in part by the assumption that the alloys used will invariably demonstrate high creep ductility. There appears to be little awareness regarding the implication(s) that creep ductility has on structural performance when mechanical or metallurgical notches (e.g., welds) are present in the component design or fabricated component. This reduced awareness regarding the role of ductility is largely because low alloy CrMo steels used for very many years typically were creep ductile. This paper focuses on the structural response from selected tests that have been commissioned or executed by EPRI over the last decade. The results of these tests demonstrate unambiguously the importance that creep ductility has on long-term, time-dependent behavior. This is the second part of a two-part paper; Part I reviewed the selected tests and discussed them from a mechanical perspective. The association of performance with specific microstructural features is briefly reviewed in this paper and the remaining gaps are highlighted for consideration among the international community.
Quantification of Dynamic Recrystallization and Its Relation to Imposed Mechanical Energy and Ductility Dip Cracking in High-Chromium Nickel Alloy Groove Welds
Authors: Singh Anil , Alexandrov Boian T. , Mills Michael J. , Luther Samuel J. , McCracken Steven L. , Tatman Jonathan K.
Published: October 2024

Ductility dip cracking (DDC) is known to occur in highly restrained welds and structural overlays made using high chromium (Cr) nickel (Ni) based filler metals in the nuclear power generation industry, resulting in costly repairs and reworks. Previous work explored the role of mechanical energy imposed by the thermo-mechanical cycle of multipass welding on DDC formation in a highly restrained Alloy 52 filler metal weld. It was hypothesized that imposed mechanical energy (IME) in the recrystallization temperature range would induce dynamic recrystallization (DRX), which is known to mitigate DDC formation. It was not shown however that IME in the recrystallization temperature range (IMERT) induced DRX. The objective of the work is to discern if a relationship between IMERT and DRX exists and quantify the amount of DRX observed in a filler metal 52 (FM-52) groove weld. DRX was analyzed and quantified using electron beam scattered diffraction (EBSD) generated inverse poll figures (IPF), grain surface area and grain aspect ratio distribution, grain orientation spread (GOS), kernel average misorientation (KAM), and grain boundary (GB) length density. From the analysis, GOS was determined to be an unsuitable criterion for quantifying DRX in multipass Ni-Cr fusion welds. Based on the observed criteria, higher IMERT regions correlate to smaller grain surface area, larger grain boundary density, and higher grain aspect ratio, which are all symptoms of DRX. High IMERT has a strong correlation with the symptoms DRX, but due to the lack of observable DRX, creating a threshold for DRX grain size, grain aspect ratio, and GB density is not possible. Future work will aim to optimize characterization criteria based on a Ni-Cr weld with large presence of DRX.
Evaluation of Directed Energy Deposition 316LSi Stainless Steel Pressure Boundary Parts
Authors: Tate Stephen , Schaeffer Ben , Barnhart Brad
Published: October 2024

Additive manufacturing is being considered for pressure boundary applications for power plant service by ASME Boiler and Pressure Vessel Code and regulators. Both existing and new plants could benefit from the reduced lead times, design flexibility, and part consolidation possible with additive manufacturing. Various ASME code committees are working towards rules and guidance for use of additive manufacturing. To further the industry's understanding, this research program was undertaken to evaluate the properties of wire arc additive manufactured 316L stainless steel. This study included microstructural characterization, chemical composition testing, mechanical testing, and nondestructive evaluation of multiple large (1600-pound (700 kg)) 316LSi stainless steel valve bodies produced using the gas metal arc directed energy deposition process followed by solution annealing. The results showed the tensile behavior over a range of temperatures was comparable to wrought material. No variation in tensile behavior was observed with change in tensile sample orientation relative to the build direction. Room temperature Charpy V-notch absorbed energy toughness was comparable to wrought material. Large grain sizes were observed in the metallographic samples, indicating that lowering the solution anneal temperature may be worthwhile. The results of surface and volumetric examination were acceptable when compared to forged material acceptance criteria. Together these results suggest that GMA-DED can produce acceptable materials properties comparable to forged materials requirements.
Investigation of Novel Nickel-Based Alloys for High Temperature Molten Chloride Salt Reactor Structural Applications
Authors: Kumar N. Naveen , Ravikumar Sonali , Donkor Boateng Twum , Song Jie , Soni Vishal , Sharma Abhishek , Dasari Sriswaroop , Viswanathan Gopal B. , Singh Harjot , Chen Qinyun , Banerjee Rajarshi , Steiner Matthew A. , Zinkle Steven J. , Muralidharan G. , Ravi Vilupanur A. , Vasudevan Vijay K.
Published: October 2024

An attempt is being made to develop novel Ni-Mo-W-Cr-Al-X alloys with ICME approach with critical experimental/simulations and processing/microstructural characterization/property evaluation and performance testing has been adopted. In this work, based on thermodynamic modeling five alloy compositions with varying Mo/W and two alloys with high tungsten modified with the addition of Al or Ti were selected and prepared. The newly developed alloys were evaluated for their response to thermal aging in the temperature range of 700 to 850 °C and corrosion in the KCl-NaCl-MgCl2 salt under suitable conditions. Thermally aged and post-corrosion test samples were characterized to ascertain phase transformations, microstructural changes and corrosion mechanisms. Al/Ti modified alloys showed significant change in hardness after 400 hours aging at 750°C, which was found to be due to the presence of fine γ’/γ” precipitates along with plate-shaped W/Mo-rich particles. These alloys show comparable molten salt corrosion resistance as commercial alloys at 750°C for 200-hour exposures. The good corrosion behavior of these alloys may be attributed to the formation of a protective multicomponent Al-or Ti-enriched oxide as well as the unique microstructure.
Assessment of a Grade 91 Steel Forging and Seamless Pipe Section After 141,000-Hours of Operation in a Superheat Outlet Header
Authors: Wang Yiyu , Zhang Wei , Wang Yanli , Feng Zhili , Siefert John , Bridges Alex , Kung Steven
Published: October 2024

In this work, two unique heats of 9Cr creep strength enhanced ferritic (CSEF) steels extracted from a retired superheat outlet header after 141,000 hours of service were evaluated. These two CSEF steels were a forging manufactured to SA-182 F91 (F91) reducer and a seamless pipe produced to SA-335 P91 (P91) pipe. Their creep deformation and fracture behavior were assessed using a lever arm creep frame integrated with in-situ high-temperature digital image correlation (DIC) system. Critical metallurgical and microstructure factors, including composition, service damage, grain matrix degradation, precipitates, and inclusions were quantitatively characterized to link the performance of the two service aged F91 and P91 CSEF steels. The creep test results show the F91 and P91 steels exhibit a large variation in creep strength and creep ductility. The F91 steel fractured at 572 hours while P91 steel fractured at 1,901 hours when subjected to a test condition of 650 °C and 100 MPa. The nominal creep strains at fracture were 12.5% (F91) and 14.5% (P91), respectively. The high-resolution DIC strain measurements reveal the local creep strain in F91 was about 50% while the local creep strain in P91 was >80%. The characterization results show that the F91 steel possessed pre-existing creep damage from its time in service, a higher fraction of inclusions, and a faster matrix grain coarsening rate. These features contribute to the observed reduction in performance for the F91 steel. The context for these findings, and the importance of metallurgical risk in an integrated life management approach will be emphasized.
Machining Methods and Their Effect on the Fatigue Performance of SA508 Gr3 Class 2 and 316L Steels
Authors: Wika Krystian K. , Waterhouse Lee , Callaghan Mark D. , Carpenter Charles , Coon David , Wright Andrew
Published: October 2024

Supercritical carbon dioxide cooling during machining has been identified as an effective measure to mitigate the risk of stress corrosion cracking in materials utilized in the primary circuit of light water reactors, particularly in pressure vessel structural steels. This study aims to compare two different cooling methods, the novel supercritical carbon dioxide and conventional high pressure soluble oil, employed during both milling and turning processes for SA508 Grade 3 Class 2 and AISI 316L steels. As the surface conditions of materials are critical to fatigue properties, such as crack initiation and endurance life, the fatigue performance of both cooling methods for each process were then evaluated and the impact on properties determined. To compare the potential benefits of supercritical carbon dioxide cooling against conventional soluble oil cooled machining, fatigue specimens were machined using industry relevant CNC machine tools. Surface finish and machining methods were standardized to produce two different specimen types, possessing dog- bone (milled) and cylindrical (turned) geometries. Force-controlled constant amplitude axial fatigue testing at various stress amplitudes was undertaken on both specimen types in an air environment and at room temperature using a stress ratio of 0.1. The fatigue performance of the supercritical carbon dioxide cooled specimens revealed substantially greater endurance lives for both SA508 and 316L materials, when compared with specimens machined using high pressure soluble oil cooling.
Development of PWHT-Free, Reduced Activation Creep-Strength Enhanced Bainitic Ferritic Steel for Large-Scale Fusion Reactor Components
Authors: Yamamoto Yukinori , Miller Roger , Graening Tim , Bhattacharya Arunodaya , Burke M. Grace
Published: October 2024

A compositional modification has been proposed to validate an alloy design which potentially eliminates the requirement of post-weld heat treatment (PWHT) while preserving the advantage of mechanical properties in a reduced activation bainitic ferritic steel based on Fe-3Cr-3W-0.2V- 0.1Ta-Mn-Si-C, in weight percent, developed at Oak Ridge National Laboratory in 2007. The alloy design includes reducing the hardness in the as-welded condition for improving toughness, while increasing the hardenability for preserving the high-temperature mechanical performance such as creep-rupture resistance in the original steel. To achieve such a design, a composition range with a reduced C content combining with an increased Mn content has been proposed and investigated. Newly proposed “modified” steel successfully achieved an improved impact toughness in the as- welded condition, while the creep-rupture performance across the weldments without PWHT demonstrated ~50% improvement of the creep strength compared to that of the original steel weldment after PWHT. The obtained results strongly support the validity of the proposed alloy design.
Influence of Recycled Asphalt Pavement Content on Air Void Distribution, Permeability, and Modulus of Base Layer
Authors: Wu Mengqi , Wen Haifang , Balasingam Muhunthan , Manahiloh Kalehiwot N.
Published: October 2024

The use of recycled materials for construction is beneficial to both the environment and the economy. Reclaimed asphalt pavement (RAP) is one of the most commonly used recycled materials. State departments of transportation allow its use in unbound base materials at different percentages. The modulus and the permeability are recognized as important parameters for base course materials because of their effect on pavement service life. Determining the effects of the percentage of RAP on the modulus and permeability of base materials that contain RAP is important for proper pavement design. This study evaluates the effects of RAP percentage on the resilient modulus and the permeability of unbound base materials. Increasing the RAP percentage increased the resilient modulus. Constant-head permeability test results indicated that increasing the RAP percentage decreased the coefficient of permeability. High-resolution X-ray computed tomography was used to study the internal structure of the test specimens. RAP mixtures had lower void ratios than virgin crushed aggregate, which explained the high resilient modulus and low permeability of RAP mixtures.
DIGITAL MARKETING IN THE CREATIVE ECONOMY
Authors: Riki Martusa  , Meythi Meythi  , Asep R. Rukmana  , Ezra Karamang
Published: October 2024

The urgency of this research is focused on Mina Padi Integrated Agriculture education in order to increase rice production and freshwater fish production by Cibahayu Village farmers as well as digital marketing training in the creative economy of making fish-based culinary that has high economic value, as well as digital-based marketing education so as to increase economic opportunities from these marketing strategies. Through this research activity, it is hoped that digital literacy related to production marketing can be a provision in utilizing existing economic opportunities. The purpose of this research activity is to provide experience and knowledge for farmers to be able to carry out the mina padi system, besides that the community is able to apply the creative economy by making fish-based culinary, and understand the digital-based production marketing process.
Mapping the Islamic Discourse on Knowledge: The Relevance of the New Islamic Discourse
Authors: Mohamed Oudihat  , Che Amnah Binti Bahari
Published: October 2024

Abstract: In the aftermath of independence, the ex-colonized Muslim countries were caught up in a comprehensive process of Westernization of Muslim life and thought. In this context, fundamental questions have been raised: What is the vision of knowledge? What is the position of the existing traditional Islamic and modern Western knowledge? This study aims to map existing trends in the interpretation of knowledge and measure the relevance of what Elmessiri calls the “New Islamic Discourse”. Descriptive, analytical, and comparative methods are used in the entire study. The first major finding is that there are seven Islamic discourses according to how they respond to critical questions. The second major finding is that the relevance of the “New Islamic Discourse” is based on five main features namely, (1) Modern science is not neutral, (2) Secularization of life and knowledge is part of the Modern crisis, (3) Islamic view of knowledge is neither modernist nor traditionalist, (4) Islamic view of knowledge is neither positivist nor relativist, and (5) Islam is a worldview that has implications for life and knowledge (on epistemology and methodology).
Emprendimiento y Discursos de Odio: Desafíos para las Víctimas del Conflicto Armado Interno en Colombia
Authors: Cárdenas Ortiz Luis Carlos
Published: October 2024

Introducción: En el contexto del prolongado conflicto armado interno en Colombia, las víctimas enfrentan desafíos únicos al intentar iniciar negocios propios. Además de las barreras habituales como la obtención de financiamiento y recursos, estas personas lidian con estigmatización y discursos de odio arraigados en la sociedad, que obstaculizan su reintegración y emprendimiento tras años de conflicto y sufrimiento. Metodología: El enfoque metodológico combinó entrevistas en profundidad con 10 víctimas del conflicto, análisis de datos económicos y revisión de literatura sobre emprendimiento en contextos postconflicto. Los participantes fueron seleccionados estratégicamente para representar diversas experiencias y geografías. Resultados: Las entrevistas revelaron barreras específicas como el acceso limitado a financiamiento y recursos, falta de capacitación empresarial y técnicas, y el impacto negativo de la estigmatización y discursos de odio en su autoconfianza como emprendedo. Discusión: El estudio enfatizó la necesidad urgente de abordar estas limitaciones mediante políticas y programas que faciliten acceso a recursos financieros, capacitación empresarial y apoyo psicosocial específicamente orientados a las víctimas del conflicto armado interno. Conclusiones: Se comprende la importancia de contrarrestar los discursos de odio y la estigmatización para crear un entorno más propicio al emprendimiento en comunidades afectadas por el conflicto.
Talk it: Tutorial support and mental health in higher education students
Authors: Quiroz Fragoso Jennifer
Published: October 2024

Introduction in this article stated that it was born within the framework of the research project where the campaign generated: “Háblalo” for its purposes, as part of the mental health care of the students of the Metropolitan Polytechnic University of Hidalgo. from 2019 to 2023. The methodology used was a longitudinal study with an eight-career program generation cohort that was developed over four years. As a discussion, part of the campaign, all university staff were instructed to be able to listen to students with their various problems, under the assumption that active listening as first psychological help can prevent risky behaviors and attitudes. As a result, the study has shown that listening as a first attention involves providing practical and non-invasive help, in addition to knowing the needs and concerns of the student. Furthermore, its conclusions allow us to visualize new lines of research around tutoring and mental health, as well as the tutoring function as a first psychological help with active listening as a prevention and action tool.
Passively-powered knee exoskeleton to reduce human effort during manual lifting
Authors:   Department of Mechanical Engineering, Faculty of Engineering University of Moratuwa, Sri Lanka, Ranaweera P. , Gopura R. ,   Department of Mechanical Engineering, Faculty of Engineering University of Moratuwa, Sri Lanka, Jayawardena S. ,   Department of Textile and Clothing Technology, University of Moratuwa, Sri Lanka, Mann G. ,   Faculty of Engineering and Applied Science, Memorial University of Newfoundland, Canada
Published: October 2024

The proposed device consists of a system of helical elastic springs bilaterally located on the shank for capturing/storing waste biomechanical energy at the knee, a cable and pulley system to transmit power from and to the knee, a pulley locking/unlocking mechanism to achieve passive control of the device operation ensures no restrictions are posed by the springs during walking and applies a pre-tension on springs to prevent slacking of the Bowden cable using a return spring. However, when the wearer performs a squatting task, the springs engage/disengage energy springs when the knee flexes over a preset angle (i.e., 60 degrees). The energy dissipated and generated at the knee joint during decent and ascent phases from biomechanical studies were recorded as 45 J and 50 J respectively for an average human [3]. Accordingly, the selected energy springs can collectively capture and return approximately 20% of biomechanical energy at the knee.
From Click to doorstep: navigating the future of retail with automated picking in Omnichannel warehousing
Authors:   Department of Transport and Logistics Management, University of Moratuwa, Sri Lanka, Wathuyaya S. , Kosgoda D.
Published: October 2024

In this era, a concept change can be seen in the omnichannel approach. In the Brick & Motors approach, customers are required to visit the retail shop to purchase products and services, while the multi-channel approach uses multiple channels but one for order-to-delivery. In the cross-channel, customers can use two or three channels simultaneously to receive a product or service. However, omnichannel represents the integration of all accessible channels (i.e., in-store, mobile, and online) and client touchpoints to provide a seamless shopping experience. Thus, the coherence of the customer journey across several touchpoints is given priority in the omnichannel strategy, as opposed to the conventional emphasis on branding across diverse digital platforms. The ease with which customers may place orders through one channel, handle payments and pickups through another channel, and receive or return goods through a third channel is made possible by this integration (ex: Amazon, Nike, Walgreens, IKEA, and ZARA). As the omnichannel strategy continues to gain traction, effective inventory management, and simplified distribution procedures are now essential components in effectively meeting consumer needs.
Betta fish classification using transfer learning and fine-tuning of CNN models
Authors: Munif Rihwan , Prahara Adhi
Published: October 2024

Betta fish, known as freshwater fighters, are in demand because of their beauty and characteristics. These betta fish such as Crowntail, Halfmoon, Doubletail, Spadetail, Plakat, Veiltail, Paradise, and Rosetail are hard to recognize without knowledge about them. Therefore, transfer learning of Convolutional Neural Network models was proposed to classify the betta fish from the image. The transfer learning process used a pre-trained model from ImageNet of VGG16, MobileNet, and InceptionV3 and fine-tuned the models on the betta fish dataset. The models were trained on 461 images, validated with 154 images, and tested on 156 images. The result shows that the InceptionV3 model excels with 0.94 accuracies compared to VGG16 and MobileNet which acquire 0.93 and 0.92 accuracy respectively. With good accuracy, the trained model can be used in betta fish recognition applications to help people easily identify betta fish from the image.