Materialia最新文献

{"title":"On the nature of variant selection along build direction in additively manufactured Ti-6Al-4V walls","authors":"Vikrant Saumitra ,&nbsp;Avinash Gonnabattula ,&nbsp;V. Anil Kumar ,&nbsp;Anand K Kanjarla","doi":"10.1016/j.mtla.2025.102500","DOIUrl":"10.1016/j.mtla.2025.102500","url":null,"abstract":"<div><div>Microstructures in additively manufactured (AM) Ti-6Al-4V components result from a complex interplay between several competing factors such as thermal gradients, cooling rates, and repeated thermal cycles. As a result, microstructures vary significantly along the build direction. While several studies reported the variations in microstructure along the build direction in terms of grain size, morphology, and crystallographic texture, the changes in variant selection (VS), resulting from the phase transformation, along the build direction have not been reported. In this work, we report on the VS along the build direction in two slender walls of Ti-6Al-4V produced using Laser-Powder Bed Fusion (L-PBF) and Wire Laser-Direct Energy Deposition (L-DED) processes. We show that while both L-DED and L-PBF samples exhibited a decline in VS throughout the build, the underlying mechanisms responsible are different. We analyzed the variant clusters in detail and observed that the type and resulting intervariant boundaries depend on the process. L-DED predominantly favored Type II (60°/⟨11¯20⟩) intervariant boundaries, along with Cluster 1 variants, whereas L-PBF samples exhibited a preference for Type IV (63.26°/⟨10 5 5 ¯3⟩) boundaries and Cluster 2 variants. Furthermore, it is shown that the presence of primarily facilitated massive transformation (<em>α</em>_m) in L-DED samples has a significant role in variant selection.</div></div>","PeriodicalId":47623,"journal":{"name":"Materialia","volume":"42 ","pages":"Article 102500"},"PeriodicalIF":2.9,"publicationDate":"2025-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144723444","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}

{"title":"Strength and electrical conductivity of Al composites with nanocrystalline W alloy reinforcements: Experiments and modeling","authors":"D. Mohanta ,&nbsp;A.K. Chaubey ,&nbsp;M. Mukherjee ,&nbsp;S. Gollapudi","doi":"10.1016/j.mtla.2025.102501","DOIUrl":"10.1016/j.mtla.2025.102501","url":null,"abstract":"<div><div>This work reports the strength and electrical conductivity of a novel Aluminium metal matrix composite (MMC) containing nanocrystalline W-20Ti alloy dispersoids. The hot-pressed Al-4 vol. %(W-20Ti) composite exhibited higher compressive yield strength than Al-4 vol. %W and Al-4 vol. %SiC composites processed under similar conditions. The Al-W20Ti composite demonstrated a 10 % higher electrical conductivity than the Al-SiC composite which could be attributed to the metallic nature of the W-20Ti dispersion. Interestingly the W-20Ti alloy dispersions, demonstrating a microhardness of 18.6 GPa, exhibited better phase and chemical stability than the unmilled W during processing of their respective MMCs. Strengthening models revealed a significant contribution of thermal expansion mismatch induced stresses to the high strength of the Al-W20Ti system.</div></div>","PeriodicalId":47623,"journal":{"name":"Materialia","volume":"43 ","pages":"Article 102501"},"PeriodicalIF":2.9,"publicationDate":"2025-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144766415","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}

{"title":"A new approach in pulsed laser deposition of VO2 (M1)-VO2 (B) nanocomposite thin films","authors":"Slimane Lafane ,&nbsp;Mokded Bachani ,&nbsp;Samira Abdelli-Messaci","doi":"10.1016/j.mtla.2025.102498","DOIUrl":"10.1016/j.mtla.2025.102498","url":null,"abstract":"<div><div>Vanadium dioxide (VO₂) is a material that has garnered significant attention owing to its unique properties of its insulator-to-metal phase transition (IMT). VO₂ can exist in different polymorphic phases, each with distinct properties. The coexistence of VO₂ (M1) and VO₂ (B) phases has attracted increasing interest due to their impacts on the IMT. Further, films containing mixed M1 and B phases are of particular interest for technological applications. In the present study, we employed pulsed laser deposition to produce mixed VO₂ (M1) and VO₂ (B) nanocomposite films on glass substrates. This was accomplished by exploring the target-substrate distance. Our findings indicate that increasing the deposition distance results in a transition from a solely VO₂ (M1) phase to a composite phase that includes both VO₂ (M1) and VO₂ (B). This transition is associated with improvements conductivity, infrared reflectivity, and the symmetry of the hysteresis loop, while maintaining the essential features of the phase transition, such as hysteresis width, contrast, and sharpness, which are related to the improvement of structural properties. This observation stands in contrast to earlier studies that suggested a reduction in the IMT strength. Accordingly, our study provides important perspectives that can greatly improve the practical application of VO₂.</div></div>","PeriodicalId":47623,"journal":{"name":"Materialia","volume":"42 ","pages":"Article 102498"},"PeriodicalIF":2.9,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144722334","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}

{"title":"Percolation network-enabled bismuth ferrite nanocomposites as a Faraday cage","authors":"Sanjeev Patil ,&nbsp;Abishek Kumar ,&nbsp;Parasuraman Swaminathan","doi":"10.1016/j.mtla.2025.102496","DOIUrl":"10.1016/j.mtla.2025.102496","url":null,"abstract":"<div><div>An absorption capable electromagnetic interference (EMI) shielding material is critical to minimize the cross-electronics interference that exists with current reflection-based materials. Bismuth ferrite (BFO), with its ferroelectric nature, provides dipoles for low frequency polarization. Silver nanowires (Ag NWs) enabled percolation network lends mobile charges for additional shielding contribution via internal reflection, which is further enhanced by the BFO-Ag heterojunctions. Thus, the dielectric losses from BFO and the high electrical conductivity of Ag NWs combine to achieve high EMI attenuation in the X band frequency range (8 – 12 GHz). This synergy enables a 38 dB (99.98%) shielding efficiency with the BFO-Ag composite with a 25 %Ag–7 5% BFO composition (wt.%) on the flexible PET substrate. This work lays the foundation for BFO-inspired metal-oxide nanocomposites towards conformal rectifying antenna (rectenna) and anti-static device applications.</div></div>","PeriodicalId":47623,"journal":{"name":"Materialia","volume":"42 ","pages":"Article 102496"},"PeriodicalIF":3.0,"publicationDate":"2025-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144696653","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}

{"title":"Ultrafast high temperature sintering of porous metal sandwich structures","authors":"Chaolumen Wu ,&nbsp;Melody M. Wang ,&nbsp;Mingqi Shuai ,&nbsp;Teng Cui ,&nbsp;Adam Barsotti ,&nbsp;X․Wendy Gu","doi":"10.1016/j.mtla.2025.102492","DOIUrl":"10.1016/j.mtla.2025.102492","url":null,"abstract":"<div><div>Porous metals are attractive engineering materials due to their high gas/liquid permeability, high strength-to-weight ratio, low density, and excellent energy absorption. Sandwiching a porous metal between two dense sheets can be used to achieve high strength, bending stiffness and impact resistance without sacrificing the lightweight nature of the porous metal. However, conventional fabrication of porous metal sandwich structures is slow, and can lead to weak interfaces between the core and sandwich sheets. In this work, a single step fabrication of sandwich-structured porous iron foams is achieved by ultrafast high temperature sintering (UHS) of iron powders. UHS realizes high temperature sintering within 40 s, resulting in strongly connected porous structures. In-situ oxidation of the outer surfaces results in dense oxide shells, forming porous iron sandwich structures. Mechanical testing of UHS sandwich-structured samples reveal significantly higher compressive and flexural strength and modulus compared to furnace-sintered porous samples with equivalent porosity.</div></div>","PeriodicalId":47623,"journal":{"name":"Materialia","volume":"42 ","pages":"Article 102492"},"PeriodicalIF":2.9,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144722333","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}

{"title":"High-quality epitaxial BaTiO3 films grown by high-vacuum chemical vapor deposition for integrated electro-optical devices","authors":"Wojciech Szmyt ,&nbsp;Jacqueline Geler-Kremer ,&nbsp;Christof Vockenhuber ,&nbsp;Arnold Müller ,&nbsp;Timo Schumann ,&nbsp;Patrik Hoffmann","doi":"10.1016/j.mtla.2025.102490","DOIUrl":"10.1016/j.mtla.2025.102490","url":null,"abstract":"<div><div>Synthesizing high-quality epitaxial BaTiO₃ (BTO) by means of high-vacuum chemical vapor deposition (HV-CVD) requires a precise control over precursor fluxes impinging onto the heated substrate surface so that the incorporation rates of all elements correspond to the BTO film stoichiometry. Moreover, overall precursor flux magnitude strongly influences the morphology of the film grown at a given substrate temperature. HV-CVD in a combinatorial mode allows to explore a wide range of fluxes over the substrate surface in a single synthesis, saving a lot of time on process optimization. Owing to the high vacuum during synthesis, the precursor trajectories are ballistic, thus the fluxes at the location on the substrate of the best film quality are analytically evaluated. The optimized conditions are transferred into a uniform deposition mode on SrTiO₃-buffered substrate for epitaxial compatibility and further fine-tuned for the improved film quality. The obtained films are characterized by SEM, EDX, XRD, AFM, ellipsometry and RBS/HI-ERDA elemental analysis. The characterization confirms that the films are stoichiometric and pure, highly oriented (XRD rocking curve FHWM &lt;1°), near-atomically smooth, and of minimal porosity (∼1–3 % void content). The results indicate that BTO films of excellent quality are achievable using this highly scalable and competitively cost-effective technique.</div></div>","PeriodicalId":47623,"journal":{"name":"Materialia","volume":"42 ","pages":"Article 102490"},"PeriodicalIF":3.0,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144672306","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}

{"title":"Three-dimensional analysis of local and dominant habit planes in a lath martensitic stainless steel","authors":"Mehdi Mosayebi ,&nbsp;Pierre-Antony Deschênes ,&nbsp;Daniel Paquet ,&nbsp;Laurent Tôn-Thât ,&nbsp;Nabil Bassim","doi":"10.1016/j.mtla.2025.102494","DOIUrl":"10.1016/j.mtla.2025.102494","url":null,"abstract":"<div><div>The three-dimensional (3D) morphology of lath martensite in a low-carbon 13Cr–4Ni stainless steel (CA6NM alloy) was reconstructed using large-volume Xe⁺ plasma focused ion beam (PFIB) serial sectioning tomography in combination with electron backscatter diffraction (EBSD). This approach enabled a detailed analysis of both dominant and local habit planes (HPs), offering new insights into their spatial distribution and variation. The dominant HP, determined by averaging the normal directions of high-angle block boundaries (BBs) within packets and across multiple prior austenite grains (PAGs), was found to lie between {111}γ and {557}γ, with an orientation of (0.51,0.52,0.66)γ. However, local HP analysis at individual BBs revealed significant deviations from both orientations in certain regions of the microstructure. 3D morphological observations indicated that bending within specific blocks directly contributed to these local HP variations. It is suggested that interactions between adjacent growing blocks, either through spatial interference and growth competition within a single packet, or hard impingement between blocks from different packets, affect growth paths, ultimately leading to block bending and the macroscopic deflection of interface planes. These findings highlight the intricate interplay between microstructural evolution and crystallographic constraints during martensitic transformation, demonstrating the effectiveness of large-scale 3D characterization in capturing complex microstructural phenomena that are difficult to resolve through conventional 2D analyses.</div></div>","PeriodicalId":47623,"journal":{"name":"Materialia","volume":"42 ","pages":"Article 102494"},"PeriodicalIF":3.0,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144672305","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}

{"title":"Advanced modeling of the ductile–brittle transition in neutron-irradiated steel: A discrete dislocation dynamics approach","authors":"Atsuo Hirano ,&nbsp;Keitaro Watanabe ,&nbsp;Akiyuki Takahashi ,&nbsp;Akiyoshi Nomoto ,&nbsp;Tomohisa Kumagai","doi":"10.1016/j.mtla.2025.102491","DOIUrl":"10.1016/j.mtla.2025.102491","url":null,"abstract":"<div><div>Reactor pressure vessel steels are embrittled by neutron irradiation during operation. Evaluating changes in the ductile–brittle transition temperature due to irradiation is crucial for maintaining the structural integrity of nuclear power plants. Therefore, we constructed and validated a dislocation model to describe the ductile–brittle transition caused by neutron irradiation in reactor pressure vessel steels. Macroscopic and microscopic cracks near the tip of the crack were assumed based on the brittle fracture mechanism of the steel material. The behavior of the microscopic cracks that interacted with the dislocations emitted from the cracks was investigated using discrete dislocation dynamics. The proposed model reproduced two fracture behaviors: brittle and non-brittle. In the brittle mode, the microcrack fractured at the side near the macrocrack and could sequentially propagate. Conversely, it fractured at the far side in the non-brittle mode. We clarified the effect of the density, size of the carbide precipitates, and temperature on the fracture mode using our model. A brittle fracture mode could be observed if the density or size of the carbide precipitates in steel increased. We also observed the ductile–brittle transition using our model. Furthermore, the model introduced friction stress applied to the dislocations as an effect of neutron irradiation. We obtained a linear relationship between the friction stress and ductile–brittle transition temperature increment, which was experimentally validated.</div></div>","PeriodicalId":47623,"journal":{"name":"Materialia","volume":"42 ","pages":"Article 102491"},"PeriodicalIF":3.0,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144680161","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}

{"title":"Mucoadhesive drug delivery system for oral submucous fibrosis in three-dimensional multicellular and in vivo models: novel approach towards translational therapeutics","authors":"Sandhiya Viswanathan ,&nbsp;Atul Anand Bajoria ,&nbsp;Nandita Parida ,&nbsp;Rekha Rani Kokkanti ,&nbsp;Soumyajit Biswas ,&nbsp;Lavanya Prathap ,&nbsp;Abikshyeet Panda ,&nbsp;Rachna Rath ,&nbsp;Srinivas Patnaik","doi":"10.1016/j.mtla.2025.102493","DOIUrl":"10.1016/j.mtla.2025.102493","url":null,"abstract":"<div><h3>Objective</h3><div>This study aimed to develop and evaluate protease enzyme-based mucoadhesive buccal patches—Patch B (bromelain alone) and Patch C (bromelain with collagenase)—for the non-invasive management of Oral Submucous Fibrosis (OSMF).</div></div><div><h3>Study design</h3><div>The physicochemical properties, enzymatic activity, and therapeutic efficacy of the patches were analyzed. Arecoline was used to induce fibrosis and inflammation in a 3D co-culture model of KB-3–1 oral cancer cells and McCoy fibroblasts, mimicking the OSMF microenvironment. An OSMF-induced rabbit model was used to assess clinical outcomes.</div></div><div><h3>Results</h3><div>Patch B (pH 6.8–7.03) and Patch C (pH 5.92–6.98) exhibited rapid hydration and equilibrium swelling. Patch C showed enhanced collagen degradation due to synergistic enzymatic activity, while Patch B had superior biocompatibility (0.57 % haemolysis) and retained bromelain activity after six months. In the 3D co-culture model, arecoline-induced upregulation of MMP-2, MMP-9, IL-6, and collagen type IV was significantly downregulated by both patches, demonstrating their anti-inflammatory and anti-fibrotic potential. In vivo, the patches improved mouth opening and reduced the severity of fibrosis, as confirmed by histopathological analysis, which showed significant reductions in collagen deposition. Patch B demonstrated selective cytotoxicity toward cancer cells, with minimal impact on normal fibroblasts.</div></div><div><h3>Conclusion</h3><div>Bromelain-based buccal patches provide a targeted, non-invasive therapeutic approach for OSMF by reducing fibrosis and inflammation while minimizing systemic effects. Due to their effectiveness and safety profile in preclinical animals, these patches provide significant translational potential for future human clinical trials and non-surgical therapy of OSMF.</div></div>","PeriodicalId":47623,"journal":{"name":"Materialia","volume":"42 ","pages":"Article 102493"},"PeriodicalIF":3.0,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144702322","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}

{"title":"Powder spreading defects and their impact to porosity and form deviations","authors":"Caroline E. Massey,&nbsp;Christopher J. Saldaña","doi":"10.1016/j.mtla.2025.102489","DOIUrl":"10.1016/j.mtla.2025.102489","url":null,"abstract":"<div><div>Laser powder bed fusion (PBF-LB) provides an opportunity for high mix low volume parts at the expense of needing fine-tuned process parameters. The interaction between the powder bed quality and the lasing process has been understudied in literature. Spatter, superelevation, recoater selection, and wear on the recoater blade can all influence the spread profile. These defects can subsequently impact the porosity and geometric accuracy of the part. In the present work, the significance of the size of the wear on previously used recoater blades was investigated for its impact on the part’s geometric accuracy and resultant porosity profile. Laser line profilometry was employed to measure the topography deviations in the powder bed caused by spreading with a worn recoater. Lightly damaged recoater induced topography deviations were not seen to cause significant surface swelling on the part, whereas instances of heavier recoater damage were. The influence of recoater damage on the porosity profile was difficult to assess given the process parameters. The results of this study seek to inform the operator of the size criticality of recoater damage and its resultant impact on part and build quality.</div></div>","PeriodicalId":47623,"journal":{"name":"Materialia","volume":"42 ","pages":"Article 102489"},"PeriodicalIF":3.0,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144665560","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}