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Evaluation of Single and Duplex Plasma Treatment Applied to Aisi 409 Stainless Steel

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SSRN

SSRN 2024年

作者： do Monte e Silva, André Felipe Soares de Almeida, Larissa Solano Monteiro, Leandro Rossino, Luciana Sgarbi Nunes, Maelson Sousa Libório, Maxwell Santana de Carvalho Costa, Thércio Henrique Bandeira, Rafael Marinho de Sousa, Rômulo Ribeiro Magalhães Post-Graduate Materials Science and Engineering Program Federal University of Piauí PI Teresina Brazil Post-Graduate Program in Materials Science Federal University of São Carlos São Carlos Brazil Post-Graduate Program in Chemistry Federal University of Piauí PI Teresina Brazil School of Science and Technology Federal University of Rio Grande do Norte RN Natal Brazil Brazil Department of Mechanical Engineering Federal University of Piauí PI Teresina Brazil Brazil

The industrial landscape has witnessed a growing demand for components exhibiting superior performance and extended lifespan, especially in parts made of stainless steels like AISI 409 steel, widely used in automotive exhaust systems, heat exchangers, and lightweight structural components. This study investigates the enhancement of surface properties of AISI 409 stainless steel through cathodic cage plasma nitriding (CCPN) and cathodic cage plasma deposition (CCPD) processes, focusing on the novel implementation of duplex treatments. The research aims to improve the mechanical strength, wear resistance, and corrosion resistance of the steel by forming nitrides and vanadium nitride films on its surface. The duplex treatments, specifically N400D450 and N450D450, were found to significantly enhance the hardness of AISI 409 stainless steel, with the N450D450 sample achieving a maximum hardness of 1100 HV—a 461.22% increase compared to the untreated steel. This enhancement is attributed to the formation of a thick, uniform nitrided layer followed by a vanadium nitride film. The critical role of processing order was highlighted, with the sequence of nitriding followed by deposition proving more effective than the reverse. Corrosion resistance was markedly improved in the duplex-treated samples. The N450D450 sample exhibited an Ecorr of -198 mV and reduced jcorr values, indicating superior resistance to corrosive environments. These results underscore the synergistic effect of combining nitriding and vanadium deposition, which optimizes the formation of protective surface layers. Overall, this study demonstrates that duplex treatments significantly enhance the surface properties of AISI 409 stainless steel, offering the potential for extended component lifespan and reduced maintenance in industrial applications. The findings suggest that careful control of process parameters and treatment sequence is essential for achieving optimal results. © 2024, The Authors. All rights

关键词： Tribology

On the equilibrium limit of liquid stability in pressurized aqueous systems

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arXiv 2024年

作者： Zarriz, Arian Journaux, Baptiste Powell-Palm, Matthew J. J. Mike Walker’66 Department of Mechanical Engineering Texas A&M University College StationTX United States Department of Department of Earth and Space Sciences University of Washington SeattleWA United States Department of Materials Science & Engineering Texas A&M University College StationTX United States Department of Biomedical Engineering Texas A&M University College StationTX United States

Phase stability, and the limits thereof, are a central concern of materials thermodynamics. However, the temperature limits of equilibrium liquid stability in chemical systems have only been widely characterized under constant (typically atmospheric) pressure conditions, whereunder these limits are represented by the eutectic. At higher pressures, the eutectic will shift in both temperature and chemical composition, opening a wide thermodynamic parameter space over which the absolute limit of liquid stability, i.e., the limit under arbitrary values of the thermodynamic forces at play (here pressure and concentration), might exist. In this work, we use isochoric freezing and melting to measure this absolute limit for the first time in several binary aqueous brines, and nodding to the etymology of "eutectic", we name it the "cenotectic" (from Greek "κοινός-τŉξĭς", meaning "universal-melt"). We discuss the implications of our findings on ocean worlds within our solar system and cold ocean exoplanets;estimate thermodynamic limits on ice crust thickness and final ocean depth (of the cenotectic or "endgame" ocean) using measured cenotectic pressures;and finally provide a generalized thermodynamic perspective on (and definition for) this fundamental thermodynamic invariant point. © 2024, CC BY-NC-ND.

关键词： Eutectics

Digital image correlation through surface patterning of skins to monitor knee motion

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Biotribology 2023年 35-36卷

作者： Coburn, Keeley Velhal, Mrudul Goenezen, Sevan Liang, Hong J. Mike Walker ’66 Department of Mechanical Engineering Texas A&M University 77843-3123 TX United States Department of Materials Science and Engineering Texas A&M University 77840 TX United States

Digital Image Correlation (DIC) systems have been used to measure surface displacement fields by tracking a pattern applied to a surface. Offering many benefits in comparison to conventional strain-measurement devices, the use of DIC has been reported in the study of tissue biomechanics and performance of joints underneath. In this study, a new method was developed to apply a quality speckle pattern on the skin of knees. Temporary tattoo paper provided a safe, easy, and quick way for pattern application to the skin without hindering its natural behavior. A pattern was developed for analyzing the knee during a squatting motion in which the field of view, system set up, and curvature of the knee were contributing factors to the development. This research is designed to prove the feasibility of using tattoo papers as patent indicators for DIC measurement. The software was able to map the entire region of the knee and measure the displacement of each area independent of other parts, thus making it easy to identify twisting and bending of the joint. Experimental results indicated that it is an effective method to accurately analyze the motion of the knee without the need of sophisticated equipment. This methodology can be used to understand how strain affects the knee during action and thus will be useful for various sports-related activities such as training and injury management. © 2023 Elsevier Ltd

关键词： Biomechanics Knee or artificial joints Non-invasive characterization Surface patterning

Minimizing finite viscosity enhances relative kinetic energy absorption in bistable mechanical metamaterials but only with sufficiently fine discretization: a nonlinear dynamical size effect

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arXiv 2024年

作者： Xiu, Haning Fancher, Ryan Frankel, Ian Ziemke, Patrick Fermen-Coker, Müge Begley, Matthew Boechler, Nicholas Department of Mechanical and Aerospace Engineering University of California La Jolla San DiegoCA United States Department of Mechanical Engineering University of California Santa Barbara Santa BarbaraCA United States Materials Department University of California Santa Barbara Santa BarbaraCA United States DEVCOM Army Research Laboratory Aberdeen Proving GroundMD United States Program in Materials Science and Engineering University of California La Jolla San DiegoCA United States

Bistable mechanical metamaterials have shown promise for mitigating the harmful consequences of impact by converting kinetic energy into stored strain energy, offering an alternative and potentially synergistic approach to conventional methods of attenuating energy transmission. In this work, we numerically study the dynamic response of a one-dimensional bistable metamaterial struck by a high speed impactor (where the impactor velocity is commensurate with the sound speed), using the peak kinetic energy experienced at midpoint of the metamaterial compared to that in an otherwise identical linear system as our performance metric. We make five key findings: 1) The bistable material can counter-intuitively perform better (to nearly 103× better than the linear system) as the viscosity decreases (but remains finite), but only when sufficiently fine discretization has been reached (i.e. the system approaches sufficiently close to the continuum limit);2) This discretization threshold is sharp, and depends on the viscosity present;3) The bistable materials can also perform significantly worse than linear systems (for low discretization and viscosity or zero viscosity);4) The dependence on discretization stems from the partition of energy into trains of solitary waves that have pulse lengths proportional to the unit cell size, where, with intersite viscosity, the solitary wave trains induce high velocity gradients and thus enhanced damping compared to linear, and low-unit-cell-number bistable, materials;and 5) When sufficiently fine discretization has been reached at low viscosities, the bistable system outperforms the linear one for a wide range of impactor conditions. The first point is particularly important, as it shows the existence of a nonlinear dynamical "size effect", where, given a protective layer of some thickness and otherwise identical quasi-static mechanical properties and total mass, e.g., a 1 mm thick layer having 200 unit cells of 5 µm thickness is predicte

关键词： Kinetic energy

Corrigendum to “Time-course concentration of ethanol, acetaldehyde and acetate in rat brain dialysate following alcohol self-administration” [Alcohol 123 (2025) 69–76]

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Alcohol 2025年 125卷 53-54页

作者： Tse-Ang Lee Hongjoo J. Lee Regina A. Mangieri Rueben Gonzales Heba Ajmal Tanya Hutter Department of Mechanical Engineering The University of Texas at Austin Austin TX 78712 USA Department of Psychology The University of Texas at Austin Austin TX 78712 USA College of Pharmacy Division of Pharmacology and Toxicology The University of Texas at Austin Austin TX 78712 USA Department of Neuroscience The University of Texas at Austin Austin TX 78712 USA Materials Science and Engineering Program and Texas Materials Institute The University of Texas at Austin Austin TX 78712 USA

Recent Advancements in Nanophotonics for Optofluidics

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arXiv 2024年

作者： Yang, Sen Hong, Chuchuan Zhu, Guodong Anyika, Theodore Hong, Ikjun Ndukaife, Justus C. Institute of Physics Chinese Academy of Sciences Beijing National Laboratory for Condensed Matter Physics Beijing100190 China Department of Chemistry Department of Materials Science and Engineering Northwestern University EvanstonIL60208 United States Department of Electrical and Computer Engineering Vanderbilt University NashvilleTN37235 United States Department of Mechanical Engineering Vanderbilt University NashvilleTN37235 United States Interdisciplinary Materials Science Program Vanderbilt University NashvilleTN37240 United States

Optofluidics is dedicated to achieving integrated control of particle and fluid motion, particularly on the micrometer scale, by utilizing light to direct fluid flow and particle motion. The field has seen significant growth recently, driven by the concerted efforts of researchers across various scientific disciplines, notably for its successful applications in biomedical science. In this review, we explore a range of optofluidic architectures developed over the past decade, with a primary focus on mechanisms for precise control of micro and nanoscale biological objects and their applications in sensing. Regarding nanoparticle manipulation, we delve into mechanisms based on optical nanotweezers using nanolocalized light fields and light-based hybrid effects with dramatically improved performance and capabilities. In the context of sensing, we emphasize those works that used optofluidics to aggregate molecules or particles to promote sensing and detection. Additionally, we highlight emerging research directions, encompassing both fundamental principles and practical applications in the field. Copyright © 2024, The Authors. All rights reserved.

关键词： Flow of fluids

Accelerating CALPHAD-based Phase Diagram Predictions in Complex Alloys Using Universal Machine Learning Potentials: Opportunities and Challenges

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arXiv 2024年

作者： Zhu, Siya Sariturk, Doguhan Arróyave, Raymundo Department of Materials Science and Engineering Texas A&M University College StationTX77843 United States J. Mike Walker’66 Department of Mechanical Engineering Texas A&M University College StationTX77843 United States Wm Michael Barnes’64 Department of Industrial and Systems Engineering Texas A&M University College StationTX77843 United States

Accurate phase diagram prediction is crucial for understanding alloy thermodynamics and advancing materials design. While traditional CALPHAD methods are robust, they are resource-intensive and limited by experimentally assessed data. This work explores the use of machine learning interatomic potentials (MLIPs) such as M3GNet, CHGNet, MACE, SevenNet, and ORB to significantly accelerate phase diagram calculations by using the Alloy Theoretic Automated Toolkit (ATAT) to map calculations of the energies and free energies of atomistic systems to CALPHAD-compatible thermodynamic descriptions. Using case studies including Cr Mo, Cu Au, and Pt W, we demonstrate that MLIPs, particularly ORB, achieve computational speedups exceeding three orders of magnitude compared to DFT while maintaining phase stability predictions within acceptable accuracy. Extending this approach to liquid phases and ternary systems like Cr Mo V highlights its versatility for high-entropy alloys and complex chemical spaces. This work demonstrates that MLIPs, integrated with tools like ATAT within a CALPHAD framework, provide an efficient and accurate framework for high-throughput thermodynamic modeling, enabling rapid exploration of novel alloy systems. While many challenges remain to be addressed, the accuracy of some of these MLIPs (ORB in particular) are on the verge of paving the way toward high-throughput generation of CALPHAD thermodynamic descriptions of multi-component, multi-phase alloy systems. © 2024, CC BY.

关键词： Free energy

Accelerating CALPHAD-Based Phase Diagram Predictions in Complex Alloys Using Universal Machine Learning Potentials: Opportunities and Challenges

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SSRN

SSRN 2024年

Accurate phase diagram prediction is crucial for understanding alloy thermodynamics and advancing materials design. While traditional CALPHAD methods are robust, they are resource-intensive and limited by experimentally assessed data. This work explores the use of machine learning interatomic potentials (MLIPs) such as M3GNet, CHGNet, MACE, SevenNet, and ORB to significantly accelerate phase diagram calculations by using the Alloy Theoretic Automated Toolkit (ATAT) to map calculations of the energies and free energies of atomistic systems to CALPHAD-compatible thermodynamic descriptions. Using case studies including Cr Mo, Cu Au, and Pt W, we demonstrate that MLIPs, particularly ORB, achieve computational speedups exceeding three orders of magnitude compared to DFT while maintaining phase stability predictions within acceptable accuracy. Extending this approach to liquid phases and ternary systems like Cr-Mo-V highlights its versatility for high-entropy alloys and complex chemical spaces. This work demonstrates that MLIPs, integrated with tools like ATAT within a CALPHAD framework, provide an efficient and accurate framework for high-throughput thermodynamic modeling, enabling rapid exploration of novel alloy systems. While many challenges remain to be addressed, the accuracy of some of these MLIPs (ORB in particular) are on the verge of paving the way toward high-throughput generation of CALPHAD thermodynamic descriptions of multi-component, multi-phase alloy systems. © 2024, The Authors. All rights reserved.

关键词： Free energy

Plasmonic Nanolaser by Silver Nanowire Embedded in CsPbBr3 Quantum Dots

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Plasmonic Nanolaser by Silver Nanowire Embedded in CsPbBr3 Q...

JSAP-OSA Joint Symposia, JSAP 2021

作者： Xing, Di Lin, Cheng-Chieh Won, Phillip Xiang, Rong Chen, Tzu-Pei A. Kamal, A. Syazwan Lee, Yang-Chun Ho, Ya-Lun Maruyama, Shigeo Ko, Seung Hwan Chen, Chun-Wei Delaunay, Jean-Jacques School of Engineering The University of Tokyo Japan International Graduate Program of Molecular Science and Technology National Taiwan University Taiwan Department of Materials Science and Engineering National Taiwan University Taiwan Department of Mechanical Engineering Seoul National University Korea Republic of Center of Atomic Initiative for New Materials National Taiwan University Taiwan