Pub Date : 2024-10-30DOI: 10.1038/s41529-024-00529-8
Yang Hu, Kai Wang, Robert Spatschek
We propose a data-driven strategy for parameter selection in phase field nucleation models using machine learning and apply it to oxide nucleation in Fe-Cr alloys. A grand potential-based phase field model, incorporating Langevin noise, is employed to simulate oxide nucleation and benchmarked against the Johnson-Mehl-Avrami-Kolmogorov model. Three independent parameters in the phase field simulations (Langevin noise strength, numerical grid discretization and critical nucleation radius) are identified as essential for accurately modeling the nucleation behavior. These parameters serve as input features for machine learning classification and regression models. The classification model categorizes nucleation behavior into three nucleation density regimes, preventing invalid nucleation attempts in simulations, while the regression model estimates the appropriate Langevin noise strength, significantly reducing the need for time-consuming trial-and-error simulations. This data-driven approach improves the efficiency of parameter selection in phase field models and provides a generalizable method for simulating nucleation-driven microstructural evolution processes in various materials.
{"title":"A data-driven strategy for phase field nucleation modeling","authors":"Yang Hu, Kai Wang, Robert Spatschek","doi":"10.1038/s41529-024-00529-8","DOIUrl":"10.1038/s41529-024-00529-8","url":null,"abstract":"We propose a data-driven strategy for parameter selection in phase field nucleation models using machine learning and apply it to oxide nucleation in Fe-Cr alloys. A grand potential-based phase field model, incorporating Langevin noise, is employed to simulate oxide nucleation and benchmarked against the Johnson-Mehl-Avrami-Kolmogorov model. Three independent parameters in the phase field simulations (Langevin noise strength, numerical grid discretization and critical nucleation radius) are identified as essential for accurately modeling the nucleation behavior. These parameters serve as input features for machine learning classification and regression models. The classification model categorizes nucleation behavior into three nucleation density regimes, preventing invalid nucleation attempts in simulations, while the regression model estimates the appropriate Langevin noise strength, significantly reducing the need for time-consuming trial-and-error simulations. This data-driven approach improves the efficiency of parameter selection in phase field models and provides a generalizable method for simulating nucleation-driven microstructural evolution processes in various materials.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-11"},"PeriodicalIF":6.6,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00529-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142555537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-26DOI: 10.1038/s41529-024-00526-x
L. Brunswic, F. Angeli, S. Gin, E. D. van Hullebusch, M. Tarrago, L. Gautron, D. R. Neuville
Glass durability is one of the properties that can be affected by surface treatments such as coatings or chemical attacks. These treatments can be used to reduce the quantities of potentially toxic elements contained in glass that may be released in solution. Five surface treatments were selected: three different coatings (SnO2, TiO2, SiO2) and two acidic attacks (SO2 dealkalization and acid polishing). These treatments were performed on five glass compositions (soda-lime, borosilicate, barium silicate, opal, and lead crystal). Their effects on alteration rates and mechanisms were investigated through a single protocol (acetic acid 4%, 70 °C) simulating accelerated aging conditions for containers of beverages or food. The data collected over 1.3 years showed significant reduction of lead leaching with all treatments except acid polishing. The best reduction factor was obtained with SO2 dealkalization, which also demonstrated beneficial effects towards the retention of Ba by reducing the diffusion of alkalis.
{"title":"Surface treatments on commercial glasses: durable impact on the retention of lead, barium and boron","authors":"L. Brunswic, F. Angeli, S. Gin, E. D. van Hullebusch, M. Tarrago, L. Gautron, D. R. Neuville","doi":"10.1038/s41529-024-00526-x","DOIUrl":"10.1038/s41529-024-00526-x","url":null,"abstract":"Glass durability is one of the properties that can be affected by surface treatments such as coatings or chemical attacks. These treatments can be used to reduce the quantities of potentially toxic elements contained in glass that may be released in solution. Five surface treatments were selected: three different coatings (SnO2, TiO2, SiO2) and two acidic attacks (SO2 dealkalization and acid polishing). These treatments were performed on five glass compositions (soda-lime, borosilicate, barium silicate, opal, and lead crystal). Their effects on alteration rates and mechanisms were investigated through a single protocol (acetic acid 4%, 70 °C) simulating accelerated aging conditions for containers of beverages or food. The data collected over 1.3 years showed significant reduction of lead leaching with all treatments except acid polishing. The best reduction factor was obtained with SO2 dealkalization, which also demonstrated beneficial effects towards the retention of Ba by reducing the diffusion of alkalis.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-12"},"PeriodicalIF":6.6,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00526-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142519205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-21DOI: 10.1038/s41529-024-00527-w
Long Jin, Kun Zhang, Ming-Liang Zhu, Fu-Zhen Xuan
The low alloy bainitic steel used in reactor pressure vessels deteriorates during thermal service while the macroscopic thermodynamic parameters that cause thermal aging remains unknown. In this work, a thermal aging restructuring scheme was proposed by step-up aging the steel from 350 °C to 490 °C, with a total duration of 7500 hours. Samples from varied thickness of the steel were characterized in terms of carbides evolution and Charpy impact toughness at 20 °C. The carbide size and its fraction were statistically analyzed showing partial coarsening and dissolution during aging, while the carbide fraction was found linearly correlated with the impact energy for the first time. The critical transition temperature parameter of the aging process was found to be 470 °C for the steel. The macroscopic thermodynamic parameters, including the thermal aging time and temperature, facilitate a comprehensive understanding of the material degradation mechanism and provide a basis for long-term safety of equipment.
反应堆压力容器中使用的低合金贝氏体钢在热使用过程中会发生劣化,而导致热老化的宏观热力学参数仍然未知。在这项工作中,提出了一种热老化重组方案,将钢材从 350 °C 逐步老化到 490 °C,总持续时间为 7500 小时。对不同厚度的钢材样品进行了碳化物演变和 20 °C 时夏比冲击韧性的表征。对碳化物尺寸及其组分进行了统计分析,结果表明碳化物在时效过程中发生了部分粗化和溶解,同时首次发现碳化物组分与冲击能量呈线性相关。发现该钢的时效过程临界转变温度参数为 470 ℃。包括热老化时间和温度在内的宏观热力学参数有助于全面了解材料的降解机理,为设备的长期安全提供依据。
{"title":"Evolution of carbides and Charpy toughness in a low alloy bainitic steel during step-up aging process","authors":"Long Jin, Kun Zhang, Ming-Liang Zhu, Fu-Zhen Xuan","doi":"10.1038/s41529-024-00527-w","DOIUrl":"10.1038/s41529-024-00527-w","url":null,"abstract":"The low alloy bainitic steel used in reactor pressure vessels deteriorates during thermal service while the macroscopic thermodynamic parameters that cause thermal aging remains unknown. In this work, a thermal aging restructuring scheme was proposed by step-up aging the steel from 350 °C to 490 °C, with a total duration of 7500 hours. Samples from varied thickness of the steel were characterized in terms of carbides evolution and Charpy impact toughness at 20 °C. The carbide size and its fraction were statistically analyzed showing partial coarsening and dissolution during aging, while the carbide fraction was found linearly correlated with the impact energy for the first time. The critical transition temperature parameter of the aging process was found to be 470 °C for the steel. The macroscopic thermodynamic parameters, including the thermal aging time and temperature, facilitate a comprehensive understanding of the material degradation mechanism and provide a basis for long-term safety of equipment.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-11"},"PeriodicalIF":6.6,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00527-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142519183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The durability of polymer electrolyte fuel cells (PEFCs) in fuel cell electric vehicles is important for the shift from passenger cars to heavy-duty vehicles. The components of a PEFC, namely the proton exchange membrane (PEM), catalyst layer (CL), and gas diffusion layer (GDL), contribute to the degradation of the fuel cell performance. In this paper, we propose a method for simultaneously evaluating the degradation rates of these components by combining electrochemical characterization with operando synchrotron X-ray radiography. The open-circuit voltage, electrochemically active surface area (ECSA), and water saturation were used as the degradation indicators for the PEMs, CLs, and GDLs, respectively. The results of two accelerated stress tests (loading and start-stop cycles) after 10,000 cycles showed that the increase in water saturation owing to the loss of hydrophobicity due to carbon corrosion in the cathode GDL occurred on the same timescale as the degradation in the PEM and cathode CL. Specifically, during the load cycle AST, the cathode CL degraded with a 26% reduction in the ECSA along with the cathode GDL degradation with a 10% increase in water saturation. This suggests that more efforts should be devoted to studies on the durability of GDLs for heavy-duty applications.
{"title":"Simultaneous accelerated stress testing of membrane electrode assembly components in polymer electrolyte fuel cells","authors":"Wataru Yoshimune, Akihiko Kato, Tetsuichiro Hayakawa, Satoshi Yamaguchi, Satoru Kato","doi":"10.1038/s41529-024-00524-z","DOIUrl":"10.1038/s41529-024-00524-z","url":null,"abstract":"The durability of polymer electrolyte fuel cells (PEFCs) in fuel cell electric vehicles is important for the shift from passenger cars to heavy-duty vehicles. The components of a PEFC, namely the proton exchange membrane (PEM), catalyst layer (CL), and gas diffusion layer (GDL), contribute to the degradation of the fuel cell performance. In this paper, we propose a method for simultaneously evaluating the degradation rates of these components by combining electrochemical characterization with operando synchrotron X-ray radiography. The open-circuit voltage, electrochemically active surface area (ECSA), and water saturation were used as the degradation indicators for the PEMs, CLs, and GDLs, respectively. The results of two accelerated stress tests (loading and start-stop cycles) after 10,000 cycles showed that the increase in water saturation owing to the loss of hydrophobicity due to carbon corrosion in the cathode GDL occurred on the same timescale as the degradation in the PEM and cathode CL. Specifically, during the load cycle AST, the cathode CL degraded with a 26% reduction in the ECSA along with the cathode GDL degradation with a 10% increase in water saturation. This suggests that more efforts should be devoted to studies on the durability of GDLs for heavy-duty applications.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-9"},"PeriodicalIF":6.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00524-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142439145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-11DOI: 10.1038/s41529-024-00522-1
Patricia Jovičević-Klug, J. Manoj Prabhakar, Cristiano Kasdorf Giesbrecht, Tim M. Schwarz, Carsten Bonnekoh, Michael Rieth, Michael Rohwerder
The effect of hydrogen diffusion and trapping was studied in a high-Cr ferrous alloy using an inverted scanning Kelvin probe and thermal desorption spectroscopy in correlation with microstructure and residual stress study. In addition, different processing of ferritic/martensitic 9Cr1WTaV alloy (EUROFER97) was tested in correlation with observed selected properties to observe induced changes in material degradation and surface. The activation energies for hydrogen traps were shown to have distinct peaks corresponding to different trapping mechanisms, including matrix dislocations and grain boundaries. For the cryogenically treated sample, an additional peak was also identified and correlated with increased carbide precipitation.
{"title":"Hydrogen diffusion and trapping in a cryogenic processed high-Cr ferrous alloy","authors":"Patricia Jovičević-Klug, J. Manoj Prabhakar, Cristiano Kasdorf Giesbrecht, Tim M. Schwarz, Carsten Bonnekoh, Michael Rieth, Michael Rohwerder","doi":"10.1038/s41529-024-00522-1","DOIUrl":"10.1038/s41529-024-00522-1","url":null,"abstract":"The effect of hydrogen diffusion and trapping was studied in a high-Cr ferrous alloy using an inverted scanning Kelvin probe and thermal desorption spectroscopy in correlation with microstructure and residual stress study. In addition, different processing of ferritic/martensitic 9Cr1WTaV alloy (EUROFER97) was tested in correlation with observed selected properties to observe induced changes in material degradation and surface. The activation energies for hydrogen traps were shown to have distinct peaks corresponding to different trapping mechanisms, including matrix dislocations and grain boundaries. For the cryogenically treated sample, an additional peak was also identified and correlated with increased carbide precipitation.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-9"},"PeriodicalIF":6.6,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00522-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142439144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-11DOI: 10.1038/s41529-024-00517-y
J. I. Ahuir-Torres, S. Jabar, P. Franciosa, D. Ceglarek, H. R. Kotadia
This study investigated the corrosion behaviour of dissimilar steel-to-aluminium laser-welded conduction, and keyhole mode (partial- and full-penetration) lap joints through electrochemical techniques and advanced microstructural characterisation. The corrosion resistance of the weld was found to be higher than the base materials, primarily due to the presence of cathodic FexAly (η-Fe2Al5, θ-Fe4Al13, β-FeAl) intermetallic compounds (IMCs) with high corrosion potential. The different micro and macro-galvanic corrosion mechanisms were found at various interfaces around the weld, resulting in localised pitting corrosion. The keyhole mode welding showed improved corrosion resistance, primarily attributed to the type, size, and distribution of IMCs.
{"title":"The microstructure-corrosion relationships in laser-welded dissimilar steel-to-aluminium joints","authors":"J. I. Ahuir-Torres, S. Jabar, P. Franciosa, D. Ceglarek, H. R. Kotadia","doi":"10.1038/s41529-024-00517-y","DOIUrl":"10.1038/s41529-024-00517-y","url":null,"abstract":"This study investigated the corrosion behaviour of dissimilar steel-to-aluminium laser-welded conduction, and keyhole mode (partial- and full-penetration) lap joints through electrochemical techniques and advanced microstructural characterisation. The corrosion resistance of the weld was found to be higher than the base materials, primarily due to the presence of cathodic FexAly (η-Fe2Al5, θ-Fe4Al13, β-FeAl) intermetallic compounds (IMCs) with high corrosion potential. The different micro and macro-galvanic corrosion mechanisms were found at various interfaces around the weld, resulting in localised pitting corrosion. The keyhole mode welding showed improved corrosion resistance, primarily attributed to the type, size, and distribution of IMCs.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-17"},"PeriodicalIF":6.6,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00517-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142439132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-03DOI: 10.1038/s41529-024-00520-3
S. Choudhary, R. G. Kelly
Micro-segregation and resulting nanoscale microstructural heterogeneities are unavoidable in wrought 7xxx aluminum alloys produced using current casting and thermomechanical processes. This study demonstrates that these nanoscale heterogeneities significantly impact pit growth in an extruded, age-hardened aluminum alloy 7075-T651. The alloy exhibits a complex microstructure with heterogeneously distributed E-Al18Mg3Cr2 dispersoids, which promote the precipitation of coarse ƞ-Mg(ZnAlCu)2 nanoparticles resulting in the formation of solute-depleted regions both within the grain interior and along the grain boundaries in dispersoid-rich areas. These alterations affect resistance to pit growth at the nanoscale, governing the transition of micro-galvanic sites into large pits with potential for crack initiation. This work underscores the necessity for modifying alloy composition and casting processes to develop superior aluminum alloys for critical applications.
{"title":"Nanoscale heterogeneities dictate corrosion pathways in a high-strength aluminum alloy","authors":"S. Choudhary, R. G. Kelly","doi":"10.1038/s41529-024-00520-3","DOIUrl":"10.1038/s41529-024-00520-3","url":null,"abstract":"Micro-segregation and resulting nanoscale microstructural heterogeneities are unavoidable in wrought 7xxx aluminum alloys produced using current casting and thermomechanical processes. This study demonstrates that these nanoscale heterogeneities significantly impact pit growth in an extruded, age-hardened aluminum alloy 7075-T651. The alloy exhibits a complex microstructure with heterogeneously distributed E-Al18Mg3Cr2 dispersoids, which promote the precipitation of coarse ƞ-Mg(ZnAlCu)2 nanoparticles resulting in the formation of solute-depleted regions both within the grain interior and along the grain boundaries in dispersoid-rich areas. These alterations affect resistance to pit growth at the nanoscale, governing the transition of micro-galvanic sites into large pits with potential for crack initiation. This work underscores the necessity for modifying alloy composition and casting processes to develop superior aluminum alloys for critical applications.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-10"},"PeriodicalIF":6.6,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00520-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142383589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Deep learning-based generative modeling demonstrates proven advantages as an effective approach in molecular discovery. This study introduces a generative-network based method called Inhibitor_Mol_VAE, which uses a variational autoencoder model to generate corrosion inhibitor molecules with targeted inhibition efficiency. We first evaluate the model’s ability to reconstruct molecules. Then, we assess the model’s ability to generate new inhibitor molecules using physiochemical properties (including MolWt, LogP, Vdw_volume, and Electronegativity). New molecules with high inhibition efficiencies at low concentrations, such as [ethoxy(methoxy)phosphoryl]-phenylmethanol and (alpha-methylamino-benzyl)-phosphonsaeure-monoaethylester are successfully discovered.
{"title":"Inhibitor_Mol_VAE: a variational autoencoder approach for generating corrosion inhibitor molecules","authors":"Haiyan Gong, Zhongheng Fu, Lingwei Ma, Dawei Zhang","doi":"10.1038/s41529-024-00518-x","DOIUrl":"10.1038/s41529-024-00518-x","url":null,"abstract":"Deep learning-based generative modeling demonstrates proven advantages as an effective approach in molecular discovery. This study introduces a generative-network based method called Inhibitor_Mol_VAE, which uses a variational autoencoder model to generate corrosion inhibitor molecules with targeted inhibition efficiency. We first evaluate the model’s ability to reconstruct molecules. Then, we assess the model’s ability to generate new inhibitor molecules using physiochemical properties (including MolWt, LogP, Vdw_volume, and Electronegativity). New molecules with high inhibition efficiencies at low concentrations, such as [ethoxy(methoxy)phosphoryl]-phenylmethanol and (alpha-methylamino-benzyl)-phosphonsaeure-monoaethylester are successfully discovered.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-17"},"PeriodicalIF":6.6,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00518-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142383555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-30DOI: 10.1038/s41529-024-00513-2
Mingjie Zhao, Wenjia Gu, Derek H. Warner
The scientific literature is rife with conflicting reports regarding the effect of dissolution on fracture. The complexity arises, in part, due to dissolution often being intertwined with various other mechanisms such as hydrogen embrittlement and the formation of debris behind an advancing crack, which can obfuscate the sole contribution of dissolution. Here, we report on the effect of dissolution when acting in isolation via the utilization of an efficient atomistic-based multiscale modeling technique and a specialized interatomic potential. Our results reveal a dual role of dissolution on crack behavior, introducing an additional layer of complexity to the mechanistic basis of environmental effects. This finding, while challenging for engineering prognosis, provides a route for engineering improved materials. Recognizing and navigating this duality could be pivotal to precluding potentially disastrous consequences in a broad array of engineering applications, from harnessing earth’s energy resources to aerospace technologies.
{"title":"The dual role of dissolution at a crack tip","authors":"Mingjie Zhao, Wenjia Gu, Derek H. Warner","doi":"10.1038/s41529-024-00513-2","DOIUrl":"10.1038/s41529-024-00513-2","url":null,"abstract":"The scientific literature is rife with conflicting reports regarding the effect of dissolution on fracture. The complexity arises, in part, due to dissolution often being intertwined with various other mechanisms such as hydrogen embrittlement and the formation of debris behind an advancing crack, which can obfuscate the sole contribution of dissolution. Here, we report on the effect of dissolution when acting in isolation via the utilization of an efficient atomistic-based multiscale modeling technique and a specialized interatomic potential. Our results reveal a dual role of dissolution on crack behavior, introducing an additional layer of complexity to the mechanistic basis of environmental effects. This finding, while challenging for engineering prognosis, provides a route for engineering improved materials. Recognizing and navigating this duality could be pivotal to precluding potentially disastrous consequences in a broad array of engineering applications, from harnessing earth’s energy resources to aerospace technologies.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-7"},"PeriodicalIF":6.6,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00513-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142329450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-29DOI: 10.1038/s41529-024-00516-z
Tiffany E. Sill, Victor Ponce, Carlos Larriuz, Ron Chertakovsky, Caroline G. Valdes, Torrick Fletcher Jr, Jakob Nielsen, Kerry Fuller, Homero Castaneda, Rachel D. Davidson, Peter M. Johnson, Sarbajit Banerjee
Corrosion of critical metal components exacts a heavy toll in terms of maintenance and replacement costs and damage to ecosystems upon failure. Polymeric barrier coatings protect against corrosion; however, design principles for modulating polymer structure to improve corrosion inhibition remain contested and elusive. Here, we examine molecular-weight-dependent differences in the efficacy of corrosion inhibition on aluminum substrates afforded by polyetherimide (PEI) coatings. Analyses of coated substrates evidence a clear trend denoting improved corrosion inhibition for higher weighted-average molecular weight (MW) PEI. The more rigid and entangled macromolecular network of higher-MW variants exhibit stable impedance values, |Z|0.01 Hz ca. 1010 Ω/cm2, upon extended immersion in brine media, whereas lower-MW variants are readily hydrated and disentangled resulting in a significant reduction in impedance values. Results illuminate mechanistic understanding of molecular-weight-dependence in corrosion inhibition, advance a framework for considering the dynamical evolution of secondary structure, and exemplify generalizable design principles for corrosion inhibition.
{"title":"Mechanistic elucidation of the molecular weight dependence of corrosion inhibition afforded by polyetherimide coatings","authors":"Tiffany E. Sill, Victor Ponce, Carlos Larriuz, Ron Chertakovsky, Caroline G. Valdes, Torrick Fletcher Jr, Jakob Nielsen, Kerry Fuller, Homero Castaneda, Rachel D. Davidson, Peter M. Johnson, Sarbajit Banerjee","doi":"10.1038/s41529-024-00516-z","DOIUrl":"10.1038/s41529-024-00516-z","url":null,"abstract":"Corrosion of critical metal components exacts a heavy toll in terms of maintenance and replacement costs and damage to ecosystems upon failure. Polymeric barrier coatings protect against corrosion; however, design principles for modulating polymer structure to improve corrosion inhibition remain contested and elusive. Here, we examine molecular-weight-dependent differences in the efficacy of corrosion inhibition on aluminum substrates afforded by polyetherimide (PEI) coatings. Analyses of coated substrates evidence a clear trend denoting improved corrosion inhibition for higher weighted-average molecular weight (MW) PEI. The more rigid and entangled macromolecular network of higher-MW variants exhibit stable impedance values, |Z|0.01 Hz ca. 1010 Ω/cm2, upon extended immersion in brine media, whereas lower-MW variants are readily hydrated and disentangled resulting in a significant reduction in impedance values. Results illuminate mechanistic understanding of molecular-weight-dependence in corrosion inhibition, advance a framework for considering the dynamical evolution of secondary structure, and exemplify generalizable design principles for corrosion inhibition.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-13"},"PeriodicalIF":6.6,"publicationDate":"2024-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00516-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142329439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}