Pub Date : 2024-08-28DOI: 10.1038/s41529-024-00499-x
Rajnikant V. Umretiya, Haozheng Qu, Liang Yin, Timothy B. Jurewicz, Vipul K. Gupta, Marija Drobnjak, Michael P. Knussman, Andrew K. Hoffman, Raul B. Rebak
Iron-Chromium-Aluminum (FeCrAl) alloys are candidate materials for the cladding of light water reactor (LWR) fuels. The FeCrAl alloys in general range in Cr composition from 12% (C26M) to 21% (APMT). In this work, the general corrosion behavior of Additively Manufactured (AM) C26M coupons was compared to the behavior of traditional Powder Metallurgy (PM) coupons. Immersion testing were conducted for 12 months at 288 °C and 330 °C in pure water containing either oxygen or hydrogen. Results show that the mass change of AM specimens in hydrogenated water was like the mass change of PM specimens. In oxygenated water, the mass change of AM coupons was higher and less reproducible than for the PM coupons. Porosity in the AM specimens makes their behavior less predictable in high-temperature water.
{"title":"Corrosion behavior of additively manufactured FeCrAl in out-of-pile light water reactor environments","authors":"Rajnikant V. Umretiya, Haozheng Qu, Liang Yin, Timothy B. Jurewicz, Vipul K. Gupta, Marija Drobnjak, Michael P. Knussman, Andrew K. Hoffman, Raul B. Rebak","doi":"10.1038/s41529-024-00499-x","DOIUrl":"10.1038/s41529-024-00499-x","url":null,"abstract":"Iron-Chromium-Aluminum (FeCrAl) alloys are candidate materials for the cladding of light water reactor (LWR) fuels. The FeCrAl alloys in general range in Cr composition from 12% (C26M) to 21% (APMT). In this work, the general corrosion behavior of Additively Manufactured (AM) C26M coupons was compared to the behavior of traditional Powder Metallurgy (PM) coupons. Immersion testing were conducted for 12 months at 288 °C and 330 °C in pure water containing either oxygen or hydrogen. Results show that the mass change of AM specimens in hydrogenated water was like the mass change of PM specimens. In oxygenated water, the mass change of AM coupons was higher and less reproducible than for the PM coupons. Porosity in the AM specimens makes their behavior less predictable in high-temperature water.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-8"},"PeriodicalIF":6.6,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00499-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142091197","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 : 2024-08-28DOI: 10.1038/s41529-024-00506-1
Krishna C. Polavaram, Sai Kalyan Evani, Sean M. Drewry, Elena Tajuelo Rodriguez, Mohammed G. Alnaggar, Christopher J. Wetteland, Katharine Page, John S. Popovics, Kurt E. Sickafus, Yann Le Pape, Nishant Garg
Nuclear power plants are aging around the world, and a precise assessment of irradiation damage in their components is needed. One key component, concrete, and specifically the silicates in its aggregates, can undergo significant expansion upon neutron radiation, which can lead to cracking and, ultimately, structural failure. However, assessing and predicting the extent of damage via neutron radiation is challenging due to reasons such as residual radioactivity and, most importantly, the high time involved. Here, we evaluate whether ion radiation can be a viable surrogate. Specifically, by employing Si2+ ion radiations and a comprehensive multi-modal imaging protocol, we report mineral-specific responses for key silicates such as quartz, albite, anorthite, and microcline. We find that 10 MeV Si2+ ions result in mineral expansions that are remarkably comparable to neutron radiation equivalent expansions (R2 = 0.86, RMSE = 1.29%), opening up pathways towards rapid assessment of silicates subject to irradiation.
{"title":"Silicon ion radiation as a viable surrogate for emulating neutron radiation damage in silicates","authors":"Krishna C. Polavaram, Sai Kalyan Evani, Sean M. Drewry, Elena Tajuelo Rodriguez, Mohammed G. Alnaggar, Christopher J. Wetteland, Katharine Page, John S. Popovics, Kurt E. Sickafus, Yann Le Pape, Nishant Garg","doi":"10.1038/s41529-024-00506-1","DOIUrl":"10.1038/s41529-024-00506-1","url":null,"abstract":"Nuclear power plants are aging around the world, and a precise assessment of irradiation damage in their components is needed. One key component, concrete, and specifically the silicates in its aggregates, can undergo significant expansion upon neutron radiation, which can lead to cracking and, ultimately, structural failure. However, assessing and predicting the extent of damage via neutron radiation is challenging due to reasons such as residual radioactivity and, most importantly, the high time involved. Here, we evaluate whether ion radiation can be a viable surrogate. Specifically, by employing Si2+ ion radiations and a comprehensive multi-modal imaging protocol, we report mineral-specific responses for key silicates such as quartz, albite, anorthite, and microcline. We find that 10 MeV Si2+ ions result in mineral expansions that are remarkably comparable to neutron radiation equivalent expansions (R2 = 0.86, RMSE = 1.29%), opening up pathways towards rapid assessment of silicates subject to irradiation.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-14"},"PeriodicalIF":6.6,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00506-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142091199","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 : 2024-08-26DOI: 10.1038/s41529-024-00508-z
Qiankun Wang, Hongfang Lu
Accurately assessing the residual strength of corroded oil and gas pipelines is crucial for ensuring their safe and stable operation. Machine learning techniques have shown promise in addressing this challenge due to their ability to handle complex, non-linear relationships in data. Unlike previous studies that primarily focused on enhancing prediction accuracy through the optimization of single models, this work shifts the emphasis to a different approach: stacking ensemble learning. This study applies a stacking model composed of seven base learners and three meta-learners to predict the residual strength of pipelines using a dataset of 453 instances. Automated hyperparameter tuning libraries are utilized to search for optimal hyperparameters. By evaluating various combinations of base learners and meta-learners, the optimal stacking configuration was determined. The results demonstrate that the stacking model, using k-nearest neighbors as the meta-learner alongside seven base learners, delivers the best predictive performance, with a coefficient of determination of 0.959. Compared to individual models, the stacking model also significantly improves generalization performance. However, the stacking model’s effectiveness on low-strength pipelines is limited due to the small sample size. Furthermore, incorporating original features into the second-layer model did not significantly enhance performance, likely because the first-layer model had already extracted most of the critical features. Given the marginal contribution of model optimization to prediction accuracy, this work offers a novel perspective for improving model performance. The findings have important practical implications for the integrity assessment of corroded pipelines.
准确评估腐蚀油气管道的残余强度对于确保其安全稳定运行至关重要。机器学习技术能够处理数据中复杂的非线性关系，因此有望解决这一难题。以往的研究主要侧重于通过优化单一模型来提高预测精度，而本研究则不同，它将重点转移到了另一种方法上：堆叠集合学习。本研究采用由七个基础学习器和三个元学习器组成的堆叠模型，使用 453 个实例的数据集预测管道的剩余强度。利用自动超参数调整库搜索最佳超参数。通过评估基础学习器和元学习器的各种组合，确定了最佳堆叠配置。结果表明，使用 k 近邻作为元学习器和七个基础学习器的堆叠模型具有最佳预测性能，决定系数为 0.959。与单个模型相比，堆叠模型还显著提高了泛化性能。不过，由于样本量较小，堆叠模型在低强度管道上的有效性受到了限制。此外，将原始特征纳入第二层模型并不能显著提高性能，这可能是因为第一层模型已经提取了大部分关键特征。鉴于模型优化对预测准确性的贡献微乎其微，这项工作为提高模型性能提供了一个新的视角。研究结果对腐蚀管道的完整性评估具有重要的现实意义。
{"title":"A novel stacking ensemble learner for predicting residual strength of corroded pipelines","authors":"Qiankun Wang, Hongfang Lu","doi":"10.1038/s41529-024-00508-z","DOIUrl":"10.1038/s41529-024-00508-z","url":null,"abstract":"Accurately assessing the residual strength of corroded oil and gas pipelines is crucial for ensuring their safe and stable operation. Machine learning techniques have shown promise in addressing this challenge due to their ability to handle complex, non-linear relationships in data. Unlike previous studies that primarily focused on enhancing prediction accuracy through the optimization of single models, this work shifts the emphasis to a different approach: stacking ensemble learning. This study applies a stacking model composed of seven base learners and three meta-learners to predict the residual strength of pipelines using a dataset of 453 instances. Automated hyperparameter tuning libraries are utilized to search for optimal hyperparameters. By evaluating various combinations of base learners and meta-learners, the optimal stacking configuration was determined. The results demonstrate that the stacking model, using k-nearest neighbors as the meta-learner alongside seven base learners, delivers the best predictive performance, with a coefficient of determination of 0.959. Compared to individual models, the stacking model also significantly improves generalization performance. However, the stacking model’s effectiveness on low-strength pipelines is limited due to the small sample size. Furthermore, incorporating original features into the second-layer model did not significantly enhance performance, likely because the first-layer model had already extracted most of the critical features. Given the marginal contribution of model optimization to prediction accuracy, this work offers a novel perspective for improving model performance. The findings have important practical implications for the integrity assessment of corroded pipelines.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-10"},"PeriodicalIF":6.6,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00508-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142091232","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 : 2024-08-22DOI: 10.1038/s41529-024-00480-8
Berenika Syrek-Gerstenkorn, Shiladitya Paul
Offshore wind energy is pivotal for achieving global renewable energy targets. As of 2022, 12% of global electricity is derived from wind and solar power, with an imperative to reach 90% renewable energy by 2050. The offshore wind industry, constituting 7.1% of global wind power, plays a central role in meeting these goals. The Global Wind Energy Alliance envisions reaching 380 GW by 2030 and 2000 GW by 2050. This paper addresses corrosion challenges in the offshore environment, emphasising sacrificial coatings as an effective mitigation strategy. By critically evaluating the latest revisions of widely used international standards such as Norsok M-501, ISO 12944, and VGBE-S-021, the study focuses on zinc- and aluminium-rich coatings that form a galvanic couple with steel, providing cathodic protection. Liquid coatings, thermally sprayed coatings, and hot-dip galvanised coatings are examined for their applicability with discussion on the advantages and limitations of these systems. Considerations of cost, environmental impact, and testing methods are crucial in selecting corrosion mitigation strategies. The review alludes to these requirements and highlights the significance of durable solutions, such as sacrificial coatings, in ensuring the long-term integrity of offshore wind structures amid the sector’s rapid expansion. Further collaborative research, involving industry and academia, is recommended to refine testing regimes and explore innovative coating solutions.
{"title":"Metallic coatings in offshore wind sector—a mini review","authors":"Berenika Syrek-Gerstenkorn, Shiladitya Paul","doi":"10.1038/s41529-024-00480-8","DOIUrl":"10.1038/s41529-024-00480-8","url":null,"abstract":"Offshore wind energy is pivotal for achieving global renewable energy targets. As of 2022, 12% of global electricity is derived from wind and solar power, with an imperative to reach 90% renewable energy by 2050. The offshore wind industry, constituting 7.1% of global wind power, plays a central role in meeting these goals. The Global Wind Energy Alliance envisions reaching 380 GW by 2030 and 2000 GW by 2050. This paper addresses corrosion challenges in the offshore environment, emphasising sacrificial coatings as an effective mitigation strategy. By critically evaluating the latest revisions of widely used international standards such as Norsok M-501, ISO 12944, and VGBE-S-021, the study focuses on zinc- and aluminium-rich coatings that form a galvanic couple with steel, providing cathodic protection. Liquid coatings, thermally sprayed coatings, and hot-dip galvanised coatings are examined for their applicability with discussion on the advantages and limitations of these systems. Considerations of cost, environmental impact, and testing methods are crucial in selecting corrosion mitigation strategies. The review alludes to these requirements and highlights the significance of durable solutions, such as sacrificial coatings, in ensuring the long-term integrity of offshore wind structures amid the sector’s rapid expansion. Further collaborative research, involving industry and academia, is recommended to refine testing regimes and explore innovative coating solutions.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-11"},"PeriodicalIF":6.6,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00480-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142021818","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}
Plasma spray-physical vapor deposition (PS-PVD) is a promising third-generation thermal barrier coatings (TBCs) technique. Feather-like columnar TBCs with excellent strain tolerance and low thermal conductivity can be achieved using PS-PVD. However, molten CMAS (CaO–MgO–Al2O3–SiO2) can penetrate coatings and accelerate PS-PVD TBCs failure due to the feather-like columnar structure. Hence, a strategy is proposed to alleviate molten CMAS corrosion. The super-hydrophobicity structure is fabricated via laser texturing on the surface of PS-PVD TBCs to repel molten CMAS wetting and spreading. Then, a thin layer of the Al-film is deposited on the laser-textured surface. Next, the Al-modified layer is in situ synthesized after vacuum heat treatment, preventing the infiltration of molten CMAS into the TBCs and reducing the coating damage. The results show that the contact angle of laser textured and Al-modified PS-PVD TBCs (LT-Al) at room temperature increased from 12.3° to 168.8°. The wetting and spreading behavior of molten CMAS of as-sprayed (AS), laser textured (LT), and LT-Al coatings is observed in situ at 1230 °C for 1800 s. The LT-Al coatings exhibited excellent CMAS corrosion resistance, attributed to the laser-textured micro-nano structures and Al-modified layer protection. The findings may be an effective approach for solving the disadvantage of PS-PVD feather-like columnar structure TBCs.
{"title":"Molten CMAS resistance strategy for PS-PVD TBCs based on laser textured and Al-modified bionic structure","authors":"Xueshi Zhuo, Xiaomao Sun, Jian Wu, Hao Dong, Peng Shen, Xiaofeng Zhang, Xuesong Mei, Jianlei Cui, Zhengjie Fan","doi":"10.1038/s41529-024-00505-2","DOIUrl":"10.1038/s41529-024-00505-2","url":null,"abstract":"Plasma spray-physical vapor deposition (PS-PVD) is a promising third-generation thermal barrier coatings (TBCs) technique. Feather-like columnar TBCs with excellent strain tolerance and low thermal conductivity can be achieved using PS-PVD. However, molten CMAS (CaO–MgO–Al2O3–SiO2) can penetrate coatings and accelerate PS-PVD TBCs failure due to the feather-like columnar structure. Hence, a strategy is proposed to alleviate molten CMAS corrosion. The super-hydrophobicity structure is fabricated via laser texturing on the surface of PS-PVD TBCs to repel molten CMAS wetting and spreading. Then, a thin layer of the Al-film is deposited on the laser-textured surface. Next, the Al-modified layer is in situ synthesized after vacuum heat treatment, preventing the infiltration of molten CMAS into the TBCs and reducing the coating damage. The results show that the contact angle of laser textured and Al-modified PS-PVD TBCs (LT-Al) at room temperature increased from 12.3° to 168.8°. The wetting and spreading behavior of molten CMAS of as-sprayed (AS), laser textured (LT), and LT-Al coatings is observed in situ at 1230 °C for 1800 s. The LT-Al coatings exhibited excellent CMAS corrosion resistance, attributed to the laser-textured micro-nano structures and Al-modified layer protection. The findings may be an effective approach for solving the disadvantage of PS-PVD feather-like columnar structure TBCs.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-10"},"PeriodicalIF":6.6,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00505-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142021841","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 : 2024-08-19DOI: 10.1038/s41529-024-00500-7
Xin Chen, Marta Pozuelo, Maxim Gussev, Matthew Chancey, Yongqiang Wang, Magdalena Balonis, Mathieu Bauchy, Gaurav Sant
There is a need for high-throughput, scale-relevant, and direct electrochemical analysis to understand the corrosion behavior and sensitivity of nuclear materials that are exposed to extreme (high pressure, temperature, and radiation exposure) environments. We demonstrate the multi-scale, multi-modal application of scanning electrochemical cell microscopy (SECCM) to electrochemically profile corrosion alterations in nuclear alloys in a microstructurally resolved manner. Particularly, we identify that both mechanically deformed and irradiated microstructures show reduced charge-transfer resistance that leads to accelerated oxidation. We highlight that the effects of mechanical deformation and irradiation are synergistic, and may in fact, superimpose each other, with implications including general-, galvanic-, and/or irradiation-activated stress-corrosion cracking. Taken together, we highlight the ability of non-destructive, electrochemical interrogations to ascertain how microstructural alterations result in changes in the corrosion tendency of a nuclear alloy: knowledge which has implications to rank, qualify and examine alloys for use in nuclear construction applications.
{"title":"Microstructurally resolved electrochemical evolution of mechanical- and irradiation-induced damage in nuclear alloys","authors":"Xin Chen, Marta Pozuelo, Maxim Gussev, Matthew Chancey, Yongqiang Wang, Magdalena Balonis, Mathieu Bauchy, Gaurav Sant","doi":"10.1038/s41529-024-00500-7","DOIUrl":"10.1038/s41529-024-00500-7","url":null,"abstract":"There is a need for high-throughput, scale-relevant, and direct electrochemical analysis to understand the corrosion behavior and sensitivity of nuclear materials that are exposed to extreme (high pressure, temperature, and radiation exposure) environments. We demonstrate the multi-scale, multi-modal application of scanning electrochemical cell microscopy (SECCM) to electrochemically profile corrosion alterations in nuclear alloys in a microstructurally resolved manner. Particularly, we identify that both mechanically deformed and irradiated microstructures show reduced charge-transfer resistance that leads to accelerated oxidation. We highlight that the effects of mechanical deformation and irradiation are synergistic, and may in fact, superimpose each other, with implications including general-, galvanic-, and/or irradiation-activated stress-corrosion cracking. Taken together, we highlight the ability of non-destructive, electrochemical interrogations to ascertain how microstructural alterations result in changes in the corrosion tendency of a nuclear alloy: knowledge which has implications to rank, qualify and examine alloys for use in nuclear construction applications.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-8"},"PeriodicalIF":6.6,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00500-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142013703","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 : 2024-08-19DOI: 10.1038/s41529-024-00504-3
Sara E. Gilson, Volodymyr Svitlyk, Andrey A. Bukaemskiy, Jonas Niessen, Theresa Lender, Gabriel L. Murphy, Maximilian Henkes, Holger Lippold, Julien Marquardt, Shavkat Akhmadaliev, Christoph Hennig, Bjoern Winkler, Thorsten Tonnesen, Lars Peters, Cornelius Fischer, Nina Huittinen
Ceramics and single crystals of LaPO4 monazite doped with Eu(III) were irradiated with 14 MeV Au5+ ions at three different fluences. Changes to crystallinity, local coordination environments, and topography were probed using grazing-incidence X-ray diffraction (GIXRD), vertical scanning interferometry (VSI), scanning electron microscopy (SEM), Raman, and luminescence spectroscopy. GIXRD data of the ceramics revealed fluence dependent amorphization. A similar level of amorphization was detected for samples irradiated with 5 × 1013 ions/cm2 and 1 × 1014 ions/cm2, whereas the sample irradiated with the highest fluence of 1 × 1015 ions/cm2 appeared slightly less amorphous. VSI showed clear swelling of entire grains at the highest ion fluence, while more localized damage to grain boundaries was detected for ceramic samples irradiated at the lowest fluence. Single crystal specimens showed no pronounced topography changes following irradiation. SEM images of the ceramic irradiated at the highest fluence showed topological features indicative of grain surface melting. Raman and luminescence data showed a different degree of disorder in polycrystalline vs. single crystal samples. While changes to PO4 vibrational modes were observed in the ceramics, changes were more subtle or not present in the single crystals. The opposite was observed when probing the local Ln-O environment using Eu(III) luminescence, where the larger changes in terms of an elongation of the Eu-O (or La-O) bond and an increasing relative disorder with increasing fluence were observed only for the single crystals. The dissimilar trends observed in irradiated single crystals and ceramics indicate that grain boundary chemistry likely plays a significant role in the radiation response.
{"title":"Microstructural investigation of Au ion-irradiated Eu-doped LaPO4 ceramics and single crystals","authors":"Sara E. Gilson, Volodymyr Svitlyk, Andrey A. Bukaemskiy, Jonas Niessen, Theresa Lender, Gabriel L. Murphy, Maximilian Henkes, Holger Lippold, Julien Marquardt, Shavkat Akhmadaliev, Christoph Hennig, Bjoern Winkler, Thorsten Tonnesen, Lars Peters, Cornelius Fischer, Nina Huittinen","doi":"10.1038/s41529-024-00504-3","DOIUrl":"10.1038/s41529-024-00504-3","url":null,"abstract":"Ceramics and single crystals of LaPO4 monazite doped with Eu(III) were irradiated with 14 MeV Au5+ ions at three different fluences. Changes to crystallinity, local coordination environments, and topography were probed using grazing-incidence X-ray diffraction (GIXRD), vertical scanning interferometry (VSI), scanning electron microscopy (SEM), Raman, and luminescence spectroscopy. GIXRD data of the ceramics revealed fluence dependent amorphization. A similar level of amorphization was detected for samples irradiated with 5 × 1013 ions/cm2 and 1 × 1014 ions/cm2, whereas the sample irradiated with the highest fluence of 1 × 1015 ions/cm2 appeared slightly less amorphous. VSI showed clear swelling of entire grains at the highest ion fluence, while more localized damage to grain boundaries was detected for ceramic samples irradiated at the lowest fluence. Single crystal specimens showed no pronounced topography changes following irradiation. SEM images of the ceramic irradiated at the highest fluence showed topological features indicative of grain surface melting. Raman and luminescence data showed a different degree of disorder in polycrystalline vs. single crystal samples. While changes to PO4 vibrational modes were observed in the ceramics, changes were more subtle or not present in the single crystals. The opposite was observed when probing the local Ln-O environment using Eu(III) luminescence, where the larger changes in terms of an elongation of the Eu-O (or La-O) bond and an increasing relative disorder with increasing fluence were observed only for the single crystals. The dissimilar trends observed in irradiated single crystals and ceramics indicate that grain boundary chemistry likely plays a significant role in the radiation response.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-11"},"PeriodicalIF":6.6,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00504-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142002624","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 : 2024-08-17DOI: 10.1038/s41529-024-00502-5
Léa Brunswic, Frédéric Angeli, Thibault Charpentier, Stéphane Gin, Pierre Asplanato, Huseyin Kaya, Seong H. Kim
Four commercial glass compositions were investigated to understand their mechanisms of alteration in light of the current and future regulations on food contact materials. Lead crystal (fine glassware), soda-lime (food and cosmetic containers), borosilicate (cookware) and barium glass (tableware) powders and slabs were altered for 3 years, in acetic acid (4% vol) at pH = 2.4 and 70 °C. The leaching solution was analyzed by ICP-AES while glass slabs were investigated by ToF-SIMS and Spectroscopic Ellipsometry. As a result, in acidic medium, the polymerization of the silicate network as well as the glass composition impacted the alteration rates and depleted depths of alkalis and earth-alkalis elements. Yet the rate of hydrolysis measured from the release of Si, remained similar under identical alteration conditions, whatever the glass structure and composition. For lead crystal glass, repolymerization of the silicate network was observed in the course of alteration.
{"title":"Comparative study of the structure and durability of commercial silicate glasses for food consumption and cosmetic packaging","authors":"Léa Brunswic, Frédéric Angeli, Thibault Charpentier, Stéphane Gin, Pierre Asplanato, Huseyin Kaya, Seong H. Kim","doi":"10.1038/s41529-024-00502-5","DOIUrl":"10.1038/s41529-024-00502-5","url":null,"abstract":"Four commercial glass compositions were investigated to understand their mechanisms of alteration in light of the current and future regulations on food contact materials. Lead crystal (fine glassware), soda-lime (food and cosmetic containers), borosilicate (cookware) and barium glass (tableware) powders and slabs were altered for 3 years, in acetic acid (4% vol) at pH = 2.4 and 70 °C. The leaching solution was analyzed by ICP-AES while glass slabs were investigated by ToF-SIMS and Spectroscopic Ellipsometry. As a result, in acidic medium, the polymerization of the silicate network as well as the glass composition impacted the alteration rates and depleted depths of alkalis and earth-alkalis elements. Yet the rate of hydrolysis measured from the release of Si, remained similar under identical alteration conditions, whatever the glass structure and composition. For lead crystal glass, repolymerization of the silicate network was observed in the course of alteration.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-12"},"PeriodicalIF":6.6,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00502-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142002632","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 : 2024-08-14DOI: 10.1038/s41529-024-00501-6
Nicolas Pinochet, Lucie Pirot-Berson, Romain Couderc, Sandrine Therias
Encapsulation polymers in terrestrial solar modules degrade due to ultraviolet radiation from the sun. To assess a polymer’s durability under UV light, accelerated aging tests can be conducted. A new LEDs device allows us to investigate the effects of temperature, irradiation, and UV source spectrum on the photooxidation mechanism and kinetics of two polyethylene-based commercial encapsulants, differentiated by the presence or absence of UV absorbers. The photooxidation rate of the polymer matrix increases as the temperature and irradiance increase between 62 and 82 °C, and 12 and 28 W.m−2, respectively. In the last case, the photooxidation rate is not proportional to the number of photons. Finally, we observed different distributions of degradation products under UVB radiation at 305 nm compared to those under UVA radiation at 365 nm. UVB photons enable Norrish reactions that are not possible with UVA alone. Special care is needed to maintain a balance between UVA and UVB photons to ensure representative durability tests. With a few adjustments to their emission spectrum, UV LED devices appear to be good candidates for accelerated aging of encapsulation polymers.
{"title":"UV LED ageing of polymers for PV cell encapsulation","authors":"Nicolas Pinochet, Lucie Pirot-Berson, Romain Couderc, Sandrine Therias","doi":"10.1038/s41529-024-00501-6","DOIUrl":"10.1038/s41529-024-00501-6","url":null,"abstract":"Encapsulation polymers in terrestrial solar modules degrade due to ultraviolet radiation from the sun. To assess a polymer’s durability under UV light, accelerated aging tests can be conducted. A new LEDs device allows us to investigate the effects of temperature, irradiation, and UV source spectrum on the photooxidation mechanism and kinetics of two polyethylene-based commercial encapsulants, differentiated by the presence or absence of UV absorbers. The photooxidation rate of the polymer matrix increases as the temperature and irradiance increase between 62 and 82 °C, and 12 and 28 W.m−2, respectively. In the last case, the photooxidation rate is not proportional to the number of photons. Finally, we observed different distributions of degradation products under UVB radiation at 305 nm compared to those under UVA radiation at 365 nm. UVB photons enable Norrish reactions that are not possible with UVA alone. Special care is needed to maintain a balance between UVA and UVB photons to ensure representative durability tests. With a few adjustments to their emission spectrum, UV LED devices appear to be good candidates for accelerated aging of encapsulation polymers.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-8"},"PeriodicalIF":6.6,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00501-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141986147","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 : 2024-08-07DOI: 10.1038/s41529-024-00497-z
Nakkyu Chae, Seungjin Seo, Richard I. Foster, Sungyeol Choi
The durability of copper (Cu) canisters against corrosion is critical for the licensing of deep geological repositories. Assessing oxic corrosion, a primary degradation mechanism, is essential for ensuring the reliability of such repositories. Due to the complex interactions influencing oxic corrosion, a comprehensive model is necessary for evaluating Cu canister corrosion. This study develops a model for the KAERI Reference Disposal System (KRS), incorporating mixed-potential theory with key O2 consumption reactions, including Cu corrosion, Cu(I) oxidation, FeS2 oxidation, aerobic microbial activity, and O2 dissolution and consumption. Simulation of 11 scenarios revealed that the representative KRS case would experience a maximum corrosion depth of 9.3 μm on the Cu canister after 2.3 years due to oxic corrosion, under conditions that are unfavorable for the initiation of pitting corrosion. These results suggest that oxic corrosion is not a threat to the isolation of spent nuclear fuels in KRS.
{"title":"Oxic corrosion model for KAERI Reference disposal system via O2 consumption reactions and mixed-potential theory","authors":"Nakkyu Chae, Seungjin Seo, Richard I. Foster, Sungyeol Choi","doi":"10.1038/s41529-024-00497-z","DOIUrl":"10.1038/s41529-024-00497-z","url":null,"abstract":"The durability of copper (Cu) canisters against corrosion is critical for the licensing of deep geological repositories. Assessing oxic corrosion, a primary degradation mechanism, is essential for ensuring the reliability of such repositories. Due to the complex interactions influencing oxic corrosion, a comprehensive model is necessary for evaluating Cu canister corrosion. This study develops a model for the KAERI Reference Disposal System (KRS), incorporating mixed-potential theory with key O2 consumption reactions, including Cu corrosion, Cu(I) oxidation, FeS2 oxidation, aerobic microbial activity, and O2 dissolution and consumption. Simulation of 11 scenarios revealed that the representative KRS case would experience a maximum corrosion depth of 9.3 μm on the Cu canister after 2.3 years due to oxic corrosion, under conditions that are unfavorable for the initiation of pitting corrosion. These results suggest that oxic corrosion is not a threat to the isolation of spent nuclear fuels in KRS.","PeriodicalId":19270,"journal":{"name":"npj Materials Degradation","volume":" ","pages":"1-12"},"PeriodicalIF":6.6,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41529-024-00497-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141939484","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}
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