Hydrated H-Apophyllite (HH-Apo) and H-carletonite (H-Car) were synthesized at 0 °C by leaching an apophyllite and a carletonite single crystal in a large surplus of 1.2 molar hydrochloric acid. The XRD powder patterns of HH-Apo and H-Car were indexed with space group symmetries of P4/ncc and I4/mcm and lattice parameters of a = 8.4872(2) Å, c = 16.8684(8) Å and a = 13.8972(3) Å, c = 20.4677(21) Å, respectively. The crystal structures were solved based on model building of the structures of the precursors and a physico-chemical characterization. Rietveld structure refinements confirmed the structure models. HH-Apo and H-Car are among the very few crystalline silicic acids whose structures have been determined and confirmed based on a structure refinement. The structure of HH-Apo contains thin silicate monolayers that can be regarded as constructed by rings of interconnected [SiO3OH] tetrahedra which form a puckered silicate layer. A sheet of water molecules is intercalated between the silicate layers. There are no direct hydrogen bonds between the silanol groups, but there are hydrogen bonds of different strengths between the terminal O atoms of the silicate layers and the intercalated water molecules. The 1H MAS NMR spectrum presents a strong signal at 4.9 ppm related to the aforementioned bonds and interactions between the water molecules, as well as a small signal at 22.5 ppm corresponding to an extremely strong hydrogen bond with d(O… O) ≈ 2.2 Å. The structure of H-Car is free of structural water and consists exclusively of microporous silicate double-layers with 4-connected [SiO4] and 3-connected [SiO3OH] tetrahedra in a ratio of 1:1 and a thickness of 9.2 Å. Neighboring layers are connected to each other by medium–strong hydrogen bonds with O…O distances of 2.56 Å. The structure of HH-Apo decays within several hours while H-Car is stable. A topotactic condensation reaction applied to H-Car forms an irregularly condensed silicate which still contains the layers in a distorted form as building blocks.
通过在大量过剩的1.2摩尔盐酸中浸泡叶蜡石和钙铈镧矿单晶，在0 °C下合成了水合H-叶蜡石（HH-Apo）和H-钙铈镧矿（H-Car）。HH-Apo 和 H-Car 的 XRD 粉末图谱的空间群对称性分别为 P4/ncc 和 I4/mcm，晶格参数分别为 a = 8.4872(2) Å, c = 16.8684(8) Å 和 a = 13.8972(3) Å, c = 20.4677(21) Å。晶体结构是在前体结构模型建立和物理化学特征描述的基础上求解的。里特维尔德结构改进证实了这些结构模型。HH-Apo 和 H-Car 是极少数通过结构细化确定和确认结构的结晶硅酸。HH-Apo 的结构包含薄薄的硅酸盐单层，可视为由相互连接的[SiO3OH]四面体环构成的皱褶硅酸盐层。硅酸盐层之间夹有一层水分子。硅醇基之间没有直接的氢键，但硅酸盐层的末端 O 原子与夹层水分子之间存在不同强度的氢键。1H MAS NMR 光谱在 4.9 ppm 处显示了一个与上述键和水分子间相互作用有关的强信号，同时在 22.5 ppm 处显示了一个与 d(O... O) ≈ 2.2 Å 的极强氢键相对应的小信号。H-Car 的结构不含结构水，完全由微孔硅酸盐双层组成，其中有 4 个相连的[SiO4]和 3 个相连的[SiO3OH]四面体，比例为 1:1，厚度为 9.2 Å，相邻层之间通过中等强度的氢键相连，O...O 间距为 2.56 Å。H-Car 的拓扑缩合反应形成了一种不规则缩合的硅酸盐，其中仍包含以扭曲形式存在的各层结构单元。
{"title":"Synthesis and Crystal Structures of Two Crystalline Silicic Acids: Hydrated H-Apophyllite, H16Si16O40 • 8–10 H2O and H-Carletonite, H32Si64O144","authors":"Bernd Marler, I. Grosskreuz","doi":"10.3390/cryst14040326","DOIUrl":"https://doi.org/10.3390/cryst14040326","url":null,"abstract":"Hydrated H-Apophyllite (HH-Apo) and H-carletonite (H-Car) were synthesized at 0 °C by leaching an apophyllite and a carletonite single crystal in a large surplus of 1.2 molar hydrochloric acid. The XRD powder patterns of HH-Apo and H-Car were indexed with space group symmetries of P4/ncc and I4/mcm and lattice parameters of a = 8.4872(2) Å, c = 16.8684(8) Å and a = 13.8972(3) Å, c = 20.4677(21) Å, respectively. The crystal structures were solved based on model building of the structures of the precursors and a physico-chemical characterization. Rietveld structure refinements confirmed the structure models. HH-Apo and H-Car are among the very few crystalline silicic acids whose structures have been determined and confirmed based on a structure refinement. The structure of HH-Apo contains thin silicate monolayers that can be regarded as constructed by rings of interconnected [SiO3OH] tetrahedra which form a puckered silicate layer. A sheet of water molecules is intercalated between the silicate layers. There are no direct hydrogen bonds between the silanol groups, but there are hydrogen bonds of different strengths between the terminal O atoms of the silicate layers and the intercalated water molecules. The 1H MAS NMR spectrum presents a strong signal at 4.9 ppm related to the aforementioned bonds and interactions between the water molecules, as well as a small signal at 22.5 ppm corresponding to an extremely strong hydrogen bond with d(O… O) ≈ 2.2 Å. The structure of H-Car is free of structural water and consists exclusively of microporous silicate double-layers with 4-connected [SiO4] and 3-connected [SiO3OH] tetrahedra in a ratio of 1:1 and a thickness of 9.2 Å. Neighboring layers are connected to each other by medium–strong hydrogen bonds with O…O distances of 2.56 Å. The structure of HH-Apo decays within several hours while H-Car is stable. A topotactic condensation reaction applied to H-Car forms an irregularly condensed silicate which still contains the layers in a distorted form as building blocks.","PeriodicalId":505131,"journal":{"name":"Crystals","volume":"27 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140361791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiwen Chen, Yuxuan Li, Zhi-Gang Li, Chao Wang, Hai Deng
Fine-grain and weak-texture magnesium alloys are the long-term development targets of lightweight structural materials. In this study, a new composite asymmetric extrusion (CAE) is developed, which, coupling with an asymmetric die and an asymmetric billet, is proposed to improve the strength–ductility of the Mg-3.8Al-1.1Sn-0.4Ca alloy. The influence of the asymmetric billet on the microstructure and mechanical properties was investigated. The findings revealed that the asymmetric billet can induce greater plastic deformation, resulting in an increase in the cumulative strain and an improved nucleation rate. The CAE sheets exhibit fine grains (4.4 μm) and a weak tilted texture (7.57 mrd). Furthermore, the asymmetric billet results in the microstructure not forming a gradient microstructure under gradient strain along the transverse direction (TD) direction. The CAE sheets exhibited good mechanical properties, with a yield strength (YS) of 253 MPa, ultimate tensile strength (UTS) of 331 MPa, and elongation (EL) of 20%. This development shows promise in achieving high-efficiency, low-cost production of magnesium alloys.
{"title":"Enhanced Strength–Ductility Synergy of Mg-Al-Sn-Ca Alloy via Composite Asymmetric Extrusion","authors":"Xiwen Chen, Yuxuan Li, Zhi-Gang Li, Chao Wang, Hai Deng","doi":"10.3390/cryst14040323","DOIUrl":"https://doi.org/10.3390/cryst14040323","url":null,"abstract":"Fine-grain and weak-texture magnesium alloys are the long-term development targets of lightweight structural materials. In this study, a new composite asymmetric extrusion (CAE) is developed, which, coupling with an asymmetric die and an asymmetric billet, is proposed to improve the strength–ductility of the Mg-3.8Al-1.1Sn-0.4Ca alloy. The influence of the asymmetric billet on the microstructure and mechanical properties was investigated. The findings revealed that the asymmetric billet can induce greater plastic deformation, resulting in an increase in the cumulative strain and an improved nucleation rate. The CAE sheets exhibit fine grains (4.4 μm) and a weak tilted texture (7.57 mrd). Furthermore, the asymmetric billet results in the microstructure not forming a gradient microstructure under gradient strain along the transverse direction (TD) direction. The CAE sheets exhibited good mechanical properties, with a yield strength (YS) of 253 MPa, ultimate tensile strength (UTS) of 331 MPa, and elongation (EL) of 20%. This development shows promise in achieving high-efficiency, low-cost production of magnesium alloys.","PeriodicalId":505131,"journal":{"name":"Crystals","volume":"1 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140362424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ligia R. Gomes, John Nicolson Low, A. Pinheiro, J. Wardell
Hydrazonylsulfones such as Bt-NHNHSO2R and their iminotautomers have been studied as optical materials and for their biological potential. In this work, a structural study has been carried out on N-(1,3-benzothiazol-2-yl)-4-(halogenobenzenesulfonyl)-hydrazides (1: X = F, Cl, Br). For (1: X = F), single-crystal X-ray diffraction, Hirshfeld surface analysis, and PIXEL calculations were conducted, while in (1: X = Cl) and (1: X = Br), only single-crystal X-ray diffraction studies were successfully conducted due to the disordering of the solvent. Each compound crystallises with two independent but similar amino tautomers in the asymmetric units: compound (1: X = F) crystallises in the monoclinic P21/c, and the isostructural pair (X: 1 = Cl and Br) crystallises in the tetragonal P-421c space group. In the most stable motif of the supramolecular arrangement, the molecules of the asymmetric unit are connected by classical N–H(hydrazinyl)···N(thiazoyl) hydrogen bonds and several face-to-face, offset π···π interactions. This motif has a very powerful influence on the crystal structure due to its direct links with the other weaker motifs. Other significant intermolecular interactions found in the structure include N–H(hydrazonyl)···O(sulfonate) bonds. Analogous intermolecular interactions were found in similar compounds, leading to the conclusion that those interactions are the most important instabilizing the solid state of hydrazonylsulfones.
{"title":"Structural Study of N-(1,3-Benzothiazol-2-yl)-4-Halobenzenesulfonylhydrazides: Hirshfeld Surface Analysis and PIXEL Calculations","authors":"Ligia R. Gomes, John Nicolson Low, A. Pinheiro, J. Wardell","doi":"10.3390/cryst14040330","DOIUrl":"https://doi.org/10.3390/cryst14040330","url":null,"abstract":"Hydrazonylsulfones such as Bt-NHNHSO2R and their iminotautomers have been studied as optical materials and for their biological potential. In this work, a structural study has been carried out on N-(1,3-benzothiazol-2-yl)-4-(halogenobenzenesulfonyl)-hydrazides (1: X = F, Cl, Br). For (1: X = F), single-crystal X-ray diffraction, Hirshfeld surface analysis, and PIXEL calculations were conducted, while in (1: X = Cl) and (1: X = Br), only single-crystal X-ray diffraction studies were successfully conducted due to the disordering of the solvent. Each compound crystallises with two independent but similar amino tautomers in the asymmetric units: compound (1: X = F) crystallises in the monoclinic P21/c, and the isostructural pair (X: 1 = Cl and Br) crystallises in the tetragonal P-421c space group. In the most stable motif of the supramolecular arrangement, the molecules of the asymmetric unit are connected by classical N–H(hydrazinyl)···N(thiazoyl) hydrogen bonds and several face-to-face, offset π···π interactions. This motif has a very powerful influence on the crystal structure due to its direct links with the other weaker motifs. Other significant intermolecular interactions found in the structure include N–H(hydrazonyl)···O(sulfonate) bonds. Analogous intermolecular interactions were found in similar compounds, leading to the conclusion that those interactions are the most important instabilizing the solid state of hydrazonylsulfones.","PeriodicalId":505131,"journal":{"name":"Crystals","volume":"32 16","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140364216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Eric Bosch, D. Unruh, Richard K. Brooks, H. Krueger, R. Groeneman
The preference in the type of halogen bond accepted by anthraquinone (C14H8O2) from two isosteric donors, namely 1,4-diiodoperfluorobenzene (C6I2F4) and 1,4-diiodoperchlorobenzene (C6I2Cl4), is reported. The two co-crystals, (C6I2F4)·(C14H8O2) and (C6I2Cl4)·(C14H8O2), are sustained primarily by I···O rather than π-type halogen bonds to form these multicomponent solids. The ability for each component to engage in two divergent halogen-bonding interactions generates a one-dimensional chain structure for each co-crystal. The bias in the halogen-bonding type is due to the difference in electrostatic potential between the carbonyl oxygen and the aromatic surface on the anthraquinone. To support this observed preference, the binding energies of the I···O halogen bond were quantified for both co-crystals by using density functional theory calculations and then compared to the interaction energy for related π-type halogen bond from previously reported structures.
{"title":"Preference in the Type of Halogen Bonding Interactions within Co-Crystals of Anthraquinone with a Pair of Isosteric Perhalobenzenes","authors":"Eric Bosch, D. Unruh, Richard K. Brooks, H. Krueger, R. Groeneman","doi":"10.3390/cryst14040325","DOIUrl":"https://doi.org/10.3390/cryst14040325","url":null,"abstract":"The preference in the type of halogen bond accepted by anthraquinone (C14H8O2) from two isosteric donors, namely 1,4-diiodoperfluorobenzene (C6I2F4) and 1,4-diiodoperchlorobenzene (C6I2Cl4), is reported. The two co-crystals, (C6I2F4)·(C14H8O2) and (C6I2Cl4)·(C14H8O2), are sustained primarily by I···O rather than π-type halogen bonds to form these multicomponent solids. The ability for each component to engage in two divergent halogen-bonding interactions generates a one-dimensional chain structure for each co-crystal. The bias in the halogen-bonding type is due to the difference in electrostatic potential between the carbonyl oxygen and the aromatic surface on the anthraquinone. To support this observed preference, the binding energies of the I···O halogen bond were quantified for both co-crystals by using density functional theory calculations and then compared to the interaction energy for related π-type halogen bond from previously reported structures.","PeriodicalId":505131,"journal":{"name":"Crystals","volume":"2 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140362669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Aluminum nitride (AlN) crystals with areas ranging from 1 mm2 to 2 mm2 were successfully grown through spontaneous nucleation at 1700 °C using a modified vapor transport method. In this approach, Cu–Al alloy served as the source of aluminum (Al), and nitrogen (N2) was employed as the nitrogen source. The morphology and crystalline quality of the AlN crystals were characterized by a stereo microscope, Raman spectrometer, photoluminescence (PL) and secondary-ion mass spectrometry (SIMS). Deposited on the graphite lid, the as-grown AlN crystals exhibited both rectangular and hexagonal shapes, identified as m-plane and c-plane AlN, respectively, based on Raman spectroscopy. The full width half maximum (FWHM) values of E2 (high) for the rectangular and hexagonal grains were measured to be 6.00 cm−1 and 6.06 cm−1, respectively, indicating high crystalline quality. However, PL and SIMS analysis indicated the presence of impurities associated with oxygen in the crystals. This paper elucidates the growth mechanism of the modified vapor transport method and highlights the role of the Cu–Al alloy in sustaining reactions at lower temperatures. The addition of copper (Cu) not only facilitates sustainable reactions, but also provides a novel perspective for the growth of AlN single crystals.
采用改进的气相传输方法，在 1700 °C 温度下通过自发成核成功地生长出了面积从 1 mm2 到 2 mm2 不等的氮化铝 (AlN) 晶体。在这种方法中，铜铝合金作为铝（Al）源，氮气（N2）作为氮源。通过立体显微镜、拉曼光谱仪、光致发光（PL）和二次离子质谱（SIMS）对 AlN 晶体的形态和结晶质量进行了表征。根据拉曼光谱，沉积在石墨盖板上的氮化铝晶体呈现矩形和六角形，分别为 m 面和 c 面氮化铝。经测量，矩形和六角形晶粒的 E2（高）全宽半最大值（FWHM）分别为 6.00 cm-1 和 6.06 cm-1，表明结晶质量很高。然而，PL 和 SIMS 分析表明晶体中存在与氧有关的杂质。本文阐明了改良气相传输法的生长机理，并强调了铜铝合金在维持低温反应中的作用。铜（Cu）的加入不仅促进了可持续反应，还为氮化铝单晶的生长提供了一个新的视角。
{"title":"Growth of Spontaneous Nucleation AlN Crystals by Al-Base Alloy Evaporation in Nitrogen Atmosphere","authors":"Xiaochun Tao, Yongkuan Xu, Jianli Chen, Yonggui Yu, Xiaofang Qi, Wencheng Ma, Zhanggui Hu","doi":"10.3390/cryst14040331","DOIUrl":"https://doi.org/10.3390/cryst14040331","url":null,"abstract":"Aluminum nitride (AlN) crystals with areas ranging from 1 mm2 to 2 mm2 were successfully grown through spontaneous nucleation at 1700 °C using a modified vapor transport method. In this approach, Cu–Al alloy served as the source of aluminum (Al), and nitrogen (N2) was employed as the nitrogen source. The morphology and crystalline quality of the AlN crystals were characterized by a stereo microscope, Raman spectrometer, photoluminescence (PL) and secondary-ion mass spectrometry (SIMS). Deposited on the graphite lid, the as-grown AlN crystals exhibited both rectangular and hexagonal shapes, identified as m-plane and c-plane AlN, respectively, based on Raman spectroscopy. The full width half maximum (FWHM) values of E2 (high) for the rectangular and hexagonal grains were measured to be 6.00 cm−1 and 6.06 cm−1, respectively, indicating high crystalline quality. However, PL and SIMS analysis indicated the presence of impurities associated with oxygen in the crystals. This paper elucidates the growth mechanism of the modified vapor transport method and highlights the role of the Cu–Al alloy in sustaining reactions at lower temperatures. The addition of copper (Cu) not only facilitates sustainable reactions, but also provides a novel perspective for the growth of AlN single crystals.","PeriodicalId":505131,"journal":{"name":"Crystals","volume":"51 21","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140363092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Dutková, M. Baláž, Jaroslav Kováč, N. Daneu, A. Kashimbetova, Jaroslav Briančin, Jaroslav Kováč, S. Kováčová, L. Čelko
In this work, a nanocomposite consisting of ternary chalcogenide CuInS2 and TiO2 was prepared and its optical and optoelectrical properties were investigated. The CuInS2/TiO2 nanocomposite was produced via one-step mechanochemical synthesis and characterized from the crystal structure, microstructural, morphology, surface, optical, and optoelectrical properties viewpoints. X-ray diffraction confirmed the presence of both components, CuInS2 and TiO2, in the nanocomposite and revealed a partial transformation of anatase to rutile. The presence of both components in the samples was also proven by Raman spectroscopy. HRTEM confirmed the nanocrystalline character of the samples as crystallites ranging from around 10 nm and up to a few tens of nanometers were found. The presence of the agglomerated nanoparticles into larger grains was proven by SEM. The measured optical properties of CuInS2, TiO2, and CuInS2/TiO2 nanocomposites demonstrate optical bandgaps of ~1.62 eV for CuInS2 and 3.26 eV for TiO2. The measurement of the optoelectrical properties showed that the presence of TiO2 in the CuInS2/TiO2 nanocomposite increased its conductivity and modified the photosensitivity depending on the ratio of the components. This study has demonstrated the possibility of preparing a CuInS2/TiO2 nanocomposite material with promising applications in optoelectronics in the visible region in an eco-friendly manner.
{"title":"Optical and Optoelectrical Properties of Ternary Chalcogenide CuInS2/TiO2 Nanocomposite Prepared by Mechanochemical Synthesis","authors":"E. Dutková, M. Baláž, Jaroslav Kováč, N. Daneu, A. Kashimbetova, Jaroslav Briančin, Jaroslav Kováč, S. Kováčová, L. Čelko","doi":"10.3390/cryst14040324","DOIUrl":"https://doi.org/10.3390/cryst14040324","url":null,"abstract":"In this work, a nanocomposite consisting of ternary chalcogenide CuInS2 and TiO2 was prepared and its optical and optoelectrical properties were investigated. The CuInS2/TiO2 nanocomposite was produced via one-step mechanochemical synthesis and characterized from the crystal structure, microstructural, morphology, surface, optical, and optoelectrical properties viewpoints. X-ray diffraction confirmed the presence of both components, CuInS2 and TiO2, in the nanocomposite and revealed a partial transformation of anatase to rutile. The presence of both components in the samples was also proven by Raman spectroscopy. HRTEM confirmed the nanocrystalline character of the samples as crystallites ranging from around 10 nm and up to a few tens of nanometers were found. The presence of the agglomerated nanoparticles into larger grains was proven by SEM. The measured optical properties of CuInS2, TiO2, and CuInS2/TiO2 nanocomposites demonstrate optical bandgaps of ~1.62 eV for CuInS2 and 3.26 eV for TiO2. The measurement of the optoelectrical properties showed that the presence of TiO2 in the CuInS2/TiO2 nanocomposite increased its conductivity and modified the photosensitivity depending on the ratio of the components. This study has demonstrated the possibility of preparing a CuInS2/TiO2 nanocomposite material with promising applications in optoelectronics in the visible region in an eco-friendly manner.","PeriodicalId":505131,"journal":{"name":"Crystals","volume":"38 15","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140362108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Aulora Williams, YubRaj Paudel, S. Mujahid, Marc Pepi, Peter Czech, H. El Kadiri, H. Rhee
The high-velocity impact of powder particles in cold-spray additively manufactured (CSAM) parts creates intersplat boundaries with regions of high dislocation densities and sub-grain structures. Upon microstructure and mechanical characterization, CSAM Aluminum 6061 showed non-uniformity with spatial variation in the microstructure and mechanical properties, affecting the overall response of the additively manufactured parts. Post-processing treatments are conducted in as-printed samples to improve particle bonding, relieve residual stresses, and improve mechanical properties. In this work, we attempt to implement the effects of grain size and distribution of smaller grains along the intersplat boundaries using the grain size distribution function and powder size information to accurately predict the deformation response of cold-sprayed material using a mean-field viscoplastic self-consistent (VPSC) model. The incorporation of an intersplat boundary term in the VPSC model resulted in a stress–strain response closely matching the experimental findings, preventing the superficially high stresses observed due to Hall–Petch effects from ultra-fine-grain structures. Likewise, the results from the grain analysis showed the combined effects of grain size, orientation, and intersplat mechanisms that captured the stresses experienced and strain accommodated by individual grains.
{"title":"Crystal Plasticity Modeling to Capture Microstructural Variations in Cold-Sprayed Materials","authors":"Aulora Williams, YubRaj Paudel, S. Mujahid, Marc Pepi, Peter Czech, H. El Kadiri, H. Rhee","doi":"10.3390/cryst14040329","DOIUrl":"https://doi.org/10.3390/cryst14040329","url":null,"abstract":"The high-velocity impact of powder particles in cold-spray additively manufactured (CSAM) parts creates intersplat boundaries with regions of high dislocation densities and sub-grain structures. Upon microstructure and mechanical characterization, CSAM Aluminum 6061 showed non-uniformity with spatial variation in the microstructure and mechanical properties, affecting the overall response of the additively manufactured parts. Post-processing treatments are conducted in as-printed samples to improve particle bonding, relieve residual stresses, and improve mechanical properties. In this work, we attempt to implement the effects of grain size and distribution of smaller grains along the intersplat boundaries using the grain size distribution function and powder size information to accurately predict the deformation response of cold-sprayed material using a mean-field viscoplastic self-consistent (VPSC) model. The incorporation of an intersplat boundary term in the VPSC model resulted in a stress–strain response closely matching the experimental findings, preventing the superficially high stresses observed due to Hall–Petch effects from ultra-fine-grain structures. Likewise, the results from the grain analysis showed the combined effects of grain size, orientation, and intersplat mechanisms that captured the stresses experienced and strain accommodated by individual grains.","PeriodicalId":505131,"journal":{"name":"Crystals","volume":"51 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140363103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The scarcity of excavated early-stage smelting sites related to copper production presents significant challenges in gaining a comprehensive understanding of the copper production process. However, the archaeological site discovered in 2018 in Daeryang-ri, Jinan-gun, Jeollabuk-do, boasts a substantial number of copper smelting remains and related slags, marking it as the first copper manufacturing production site identified on the Korean Peninsula. Consequently, this study selected 10 slag samples, chosen based on surface color and characteristics indicative of a connection to copper smelting, for scientific analysis to accurately ascertain the site’s nature. The primary component analysis of the slags indicated that CuO content ranged from 0.30 to 3.29 wt%, which, although not high, reveals significant quantities of FeO and SiO2. X-ray diffraction analysis revealed the presence of minerals such as cristobalite, along with fayalite and wüstite, commonly found in slags, varying by sample. Furthermore, microstructural observation revealed circular copper particles containing sulfur and iron, indicating the presence of copper particles in a matte state that have not been refined. This analysis suggests that the slags recovered from Jinan Daeryang-ri bear evidence of iron smelting at the site, with the slag being produced as an intermediate by-product during copper production.
{"title":"Chemical Composition, Crystal Structure, and Microstructure of Slags on the Korean Peninsula from the First Copper Production Remains of the 9th Century","authors":"Hyoryeong Choi, Yeongchun Yu, Namchul Cho","doi":"10.3390/cryst14040327","DOIUrl":"https://doi.org/10.3390/cryst14040327","url":null,"abstract":"The scarcity of excavated early-stage smelting sites related to copper production presents significant challenges in gaining a comprehensive understanding of the copper production process. However, the archaeological site discovered in 2018 in Daeryang-ri, Jinan-gun, Jeollabuk-do, boasts a substantial number of copper smelting remains and related slags, marking it as the first copper manufacturing production site identified on the Korean Peninsula. Consequently, this study selected 10 slag samples, chosen based on surface color and characteristics indicative of a connection to copper smelting, for scientific analysis to accurately ascertain the site’s nature. The primary component analysis of the slags indicated that CuO content ranged from 0.30 to 3.29 wt%, which, although not high, reveals significant quantities of FeO and SiO2. X-ray diffraction analysis revealed the presence of minerals such as cristobalite, along with fayalite and wüstite, commonly found in slags, varying by sample. Furthermore, microstructural observation revealed circular copper particles containing sulfur and iron, indicating the presence of copper particles in a matte state that have not been refined. This analysis suggests that the slags recovered from Jinan Daeryang-ri bear evidence of iron smelting at the site, with the slag being produced as an intermediate by-product during copper production.","PeriodicalId":505131,"journal":{"name":"Crystals","volume":"59 17","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140363708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
V. B. Vukkum, Taylor Sanborn, John Shepherd, S. Saptarshi, Rakesh Basu, T. Horn, R. K. Gupta
Specimens of 316 L stainless steel were printed using laser powder bed fusion (LPBF), a popular metal additive manufacturing (AM) technique, with varying island sizes. Not many researchers have considered the impact of spatter while optimizing LPBF printing parameters. In this research, the influence of spatter was considered while also investigating the effect of varied island size on the microstructure, surface roughness, microhardness, and corrosion resistance of LPBF-316 L. No correlation was observed between surface roughness or microhardness and minor variations in island size. However, a correlation was drawn between varied island sizes and porosity in LPBF-316 L. The specimens associated with larger island sizes showed significantly enhanced corrosion resistance due to fewer manufacturing defects and reduced porosity, attributed to the minimal influence of the spatter. Based on analysis, the LPBF parameters were revised, which lead to superior corrosion resistance of LPBF-316 L, attributed to high density and reduced porosity.
使用激光粉末床熔融（LPBF）打印 316 L 不锈钢试样，LPBF 是一种流行的金属增材制造（AM）技术，其岛的尺寸各不相同。很少有研究人员在优化 LPBF 打印参数时考虑飞溅物的影响。在这项研究中，在考虑飞溅物影响的同时，还研究了不同孤岛尺寸对 LPBF-316 L 的微观结构、表面粗糙度、显微硬度和耐腐蚀性的影响。然而，LPBF-316 L 中不同的晶岛尺寸和孔隙率之间存在相关性。晶岛尺寸较大的试样由于制造缺陷较少和孔隙率降低，耐腐蚀性能明显增强，这归因于飞溅物的影响最小。在分析的基础上，对 LPBF 参数进行了修改，从而使 LPBF-316 L 的耐腐蚀性能更优，这归功于高密度和孔隙率的减少。
{"title":"Influence of Spatter on Porosity, Microstructure, and Corrosion of Additively Manufactured Stainless Steel Printed Using Different Island Size","authors":"V. B. Vukkum, Taylor Sanborn, John Shepherd, S. Saptarshi, Rakesh Basu, T. Horn, R. K. Gupta","doi":"10.3390/cryst14040328","DOIUrl":"https://doi.org/10.3390/cryst14040328","url":null,"abstract":"Specimens of 316 L stainless steel were printed using laser powder bed fusion (LPBF), a popular metal additive manufacturing (AM) technique, with varying island sizes. Not many researchers have considered the impact of spatter while optimizing LPBF printing parameters. In this research, the influence of spatter was considered while also investigating the effect of varied island size on the microstructure, surface roughness, microhardness, and corrosion resistance of LPBF-316 L. No correlation was observed between surface roughness or microhardness and minor variations in island size. However, a correlation was drawn between varied island sizes and porosity in LPBF-316 L. The specimens associated with larger island sizes showed significantly enhanced corrosion resistance due to fewer manufacturing defects and reduced porosity, attributed to the minimal influence of the spatter. Based on analysis, the LPBF parameters were revised, which lead to superior corrosion resistance of LPBF-316 L, attributed to high density and reduced porosity.","PeriodicalId":505131,"journal":{"name":"Crystals","volume":"47 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140363110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Kozlovskiy, Sholpan G. Giniyatova, D. Shlimas, D. Borgekov, Ruslan M. Rspayev, M. Zdorovets
The article outlines findings from a comparative analysis of the effectiveness of doping CeO2 ceramics with a stabilizing additive Y2O3 on alterations in the strength and thermophysical parameters of ceramics under high-temperature irradiation with heavy ions comparable in energy to fission fragments of nuclear fuel, which allows, during high-temperature irradiation, to simulate radiation damage that is as similar as possible to the fission processes of nuclear fuel. During the studies, it was found that the addition of a stabilizing additive Y2O3 to the composition of CeO2 ceramics in the case of high-temperature irradiation causes an increase in stability to swelling and softening because of a decrease in the thermal expansion of the crystal lattice by 3–8 times in comparison with unstabilized CeO2 ceramics. It has been determined that the addition of a stabilizing additive Y2O3 leads not only to a rise in the resistance of the crystal structure to deformation distortions and swelling, but also to a decrease in the effect of thermal expansion of the crystal structure, which has an adverse effect on the structural ordering of CeO2 ceramics exposed to irradiation at high temperatures.
{"title":"Study of the Influence of Doping Efficiency of CeO2 Ceramics with a Stabilizing Additive Y2O3 on Changes in the Strength and Thermophysical Parameters of Ceramics under High-Temperature Irradiation with Heavy Ions","authors":"A. Kozlovskiy, Sholpan G. Giniyatova, D. Shlimas, D. Borgekov, Ruslan M. Rspayev, M. Zdorovets","doi":"10.3390/cryst14040320","DOIUrl":"https://doi.org/10.3390/cryst14040320","url":null,"abstract":"The article outlines findings from a comparative analysis of the effectiveness of doping CeO2 ceramics with a stabilizing additive Y2O3 on alterations in the strength and thermophysical parameters of ceramics under high-temperature irradiation with heavy ions comparable in energy to fission fragments of nuclear fuel, which allows, during high-temperature irradiation, to simulate radiation damage that is as similar as possible to the fission processes of nuclear fuel. During the studies, it was found that the addition of a stabilizing additive Y2O3 to the composition of CeO2 ceramics in the case of high-temperature irradiation causes an increase in stability to swelling and softening because of a decrease in the thermal expansion of the crystal lattice by 3–8 times in comparison with unstabilized CeO2 ceramics. It has been determined that the addition of a stabilizing additive Y2O3 leads not only to a rise in the resistance of the crystal structure to deformation distortions and swelling, but also to a decrease in the effect of thermal expansion of the crystal structure, which has an adverse effect on the structural ordering of CeO2 ceramics exposed to irradiation at high temperatures.","PeriodicalId":505131,"journal":{"name":"Crystals","volume":"38 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140368385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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