Bulletin of Materials Science最新文献

{"title":"Investigation of lanthanum pyrochlore-lanthanum phosphate (La2Zr2O7.LaPO4) composite coatings for high-temperature CMAS corrosion resistance in TBCs","authors":"Karthikeyan Kumarasamy,&nbsp;Umapriya Rohan,&nbsp;Manisha Vidyavathy Sudandaradoss","doi":"10.1007/s12034-026-03576-w","DOIUrl":"10.1007/s12034-026-03576-w","url":null,"abstract":"<div><p>Solid-particle contaminants rich in CaO–MgO–Al₂O₃–SiO₂ (CMAS) remain a dominant life- limiting factor for thermal-barrier coatings (TBCs) in modern gas turbines. Standard 8 wt.% yttria-stabilized zirconia (YSZ) topcoats, although thermally efficient, permit molten CMAS to penetrate their splat network, triggering phase destabilization and accelerated spallation. To counter this weakness, we designed a multilayer architecture that marries YSZ with a lanthanum pyrochlore lanthanum phosphate (LPZ) composite expected to neutralize CMAS chemically while preserving thermal insulation. Four variants were fabricated by atmospheric plasma-spraying pure YSZ (200 µm) and three hybrid stacks containing 50, 100, or 150 µm of LPZ beneath progressively thinner YSZ caps over NiCrAlY bond-coated INCONEL 718 substrates. All specimens were exposed to a 10 mg cm^-2 CMAS overlay at 1200°C for 8–48h. Pre- and post-exposure characterization employed 3-D profilometry, scanning electron microscopy with energy-dispersive spectroscopy, and X-ray diffraction. Increasing the LPZ fraction systematically reduced columnar gap width, porosity, and roughness growth. The richest LPZ coating (50 µm YSZ/150 µm LPZ) curtailed CMAS ingress to ~50 µm after 48 h one quarter of the depth measured in monolithic YSZ and retained &gt;90% of its initial hardness. X-ray analysis revealed the <i>in situ</i> formation of a dense apatite layer, Ca₃La₇(PO₃)(SiO₃)₅O₂, that sealed residual pathways and blocked further attack. The study confirms that integrating a reactive LPZ sub-layer transforms a conventional YSZ topcoat into a reactive protective layer formation, offering a viable route to longer component life and higher permissible firing temperatures in CMAS-laden environments.</p></div>","PeriodicalId":502,"journal":{"name":"Bulletin of Materials Science","volume":"49 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147561399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of structural and physical properties of members bridging Li3M2SbO6 and Li4MSbO6 by tuning M2+/M3+ (M = Co, Ni) content","authors":"S U Thapliyal,&nbsp;D K Yadav,&nbsp;S Uma","doi":"10.1007/s12034-026-03553-3","DOIUrl":"10.1007/s12034-026-03553-3","url":null,"abstract":"<div><p>Layered oxides containing redox-capable transition metals find huge application as electrode materials in lithium-ion batteries (LIBs). In the present work, a new series of rock salt superstructured oxides possessing Co²⁺/Co³⁺ and Ni²⁺/Ni³⁺ redox systems has been explored. The intermediate compositions bridging the Li₃M₂SbO₆ and Li₄MSbO₆ (M = Ni, Co) series have been investigated for their structure, optical and magnetic properties. Le Bail fittings of the PXRD patterns revealed all the compositions Li₃(Li_<i>x</i><span>({mathbf{M}}_{bf2-2{varvec{x}}}^{bf2+}{mathbf{M}}_{{varvec{x}}}^{bf3+})</span>)SbO₆ (M = Ni, Co and 0.25 ≤ <i>x</i> ≤ 0.75 for Ni and <i>x</i> = 0.75 for Co), have been stabilized in space group <i>C</i>2/<i>m</i>. The systematic evolution of cell volume confirmed uniform introduction of Ni³⁺/Co³⁺ ions with increasing Li⁺ content. The oxidation states and M³⁺/M²⁺ ratios were confirmed from XPS studies and supported by the absorbance bands in UV–visible diffuse reflectance spectra. The temperature-dependent magnetic susceptibility revealed only paramagnetic behaviour with no divergence in ZFC and FC data down to 2 K for both Ni and Co series. The effective magnetic moment decreased systematically with increasing Ni³⁺ content. Stabilization of additional compositions, Li_3.75Ni_0.50Al_0.75SbO₆, Li_3.75Zn_0.50Co_0.75SbO₆ and Li_3.75Mn_0.50Fe_0.75SbO₆ in monoclinic symmetry reinforced the flexibility of the rock salt layered superstructured oxides to produce honeycomb arrays of tailored stoichiometries for diverse applications.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":502,"journal":{"name":"Bulletin of Materials Science","volume":"49 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147561306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fly-ash-based geopolymers: leachability and solid-state NMR investigations","authors":"Athulya Nadol,&nbsp;T G Ajithkumar,&nbsp;Rashmi Singla,&nbsp;T C Alex,&nbsp;Sanjay Kumar,&nbsp;Himal Bhatt,&nbsp;M N Deo,&nbsp;Debasis Sen,&nbsp;R D Ambashta,&nbsp;R K Bajpai,&nbsp;Y C Shivakumar,&nbsp;S Manohar","doi":"10.1007/s12034-025-03487-2","DOIUrl":"10.1007/s12034-025-03487-2","url":null,"abstract":"<div><p>This study aims to explore how leaching impacts the microstructure of a selected fly ash-derived geopolymer and evaluate its potential for near-surface disposal of radioactive waste. The uniqueness of this geopolymer formulation is its ability to form an aluminosilicate network that remains resistant to structural changes upon contact with water. The leach index of base elements such as Ca, Al, Na and Si was between 11 and 13, suggesting that the formulation is superior to Portland cement or conventional hydraulic cement. Solid-state NMR reveals that the water-interacted specimen has no contamination of the zeolite phase and all the Na is incorporated into the aluminosilicate geopolymer gel network, which also confirms that the glassy network of the geopolymer is responsible for imparting low leachability of base elements from its structure, and there is no labile sodium available for exchange as in zeolites.</p></div>","PeriodicalId":502,"journal":{"name":"Bulletin of Materials Science","volume":"49 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147561315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Challenges in fabricating free-standing films of polytetrafluoroethylene and fluorinated ethylene propylene polymers for hydrogen barrier applications","authors":"Danavath Balu,&nbsp;Piyush Chandra Verma,&nbsp;Prabakaran Saravanan","doi":"10.1007/s12034-026-03555-1","DOIUrl":"10.1007/s12034-026-03555-1","url":null,"abstract":"<div><p>The safe and efficient transport of hydrogen gas is essential for advancing a hydrogen-based economy. High-pressure steel pipelines are commonly used for this purpose, but their susceptibility to hydrogen embrittlement (HE) poses a major challenge, often requiring conservative operating conditions. To overcome this, polymer coatings are being explored as a cost-effective and durable alternative to traditional metal and ceramic coatings. In this study, polytetrafluoroethylene (PTFE) and fluorinated ethylene propylene (FEP) were deposited using spin coating to develop free-standing films for hydrogen permeability testing. A total of 12 different approaches were tested to achieve successful delamination of the coatings from various substrates, including the use of sacrificial layers. However, most attempts resulted in coating failure due to issues such as solvent attack, cracking and polymer degradation during curing. As a result, quantitative hydrogen permeability measurements could not be carried out. Among the tested approaches, the ninth method showed partial success in delaminating the PTFE film, though surface cracks were still observed. Scanning electron microscopy (SEM) was used to assess the surface morphology and identify defects. These findings emphasize the need for further optimization in film fabrication techniques to produce robust, defect-free free-standing films for effective use as hydrogen permeation barriers (HPBs). From the authors’ perspective, these initial results provide valuable direction for improving coating strategies and offer a foundation for future development of polymer-based protective layers in hydrogen infrastructure applications.</p></div>","PeriodicalId":502,"journal":{"name":"Bulletin of Materials Science","volume":"49 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147561314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-variable optimization of cryogenically treated copper beryllium tool electrodes for electrical discharge machining","authors":"M Pervaz Ahmed,&nbsp;H Siddhi Jailani,&nbsp;C K Arvinda Pandian,&nbsp;J Mahashar Ali","doi":"10.1007/s12034-026-03564-0","DOIUrl":"10.1007/s12034-026-03564-0","url":null,"abstract":"<div><p>The investigation in this study pertains to the multi-objective optimization of a cryogenically treated tool electrode utilized in electrical discharge machining (EDM). A copper beryllium alloy underwent both mild and extensive cryogenic treatment processes. Subsequently, the untreated alloy, as well as the mildly and extensively treated copper beryllium alloys, were employed as electrode materials. The work piece material utilized was AISI 4140 stainless steel. The EDM process was conducted through die-sinking EDM. The optimization of various input parameters (amperes current, duty factor and electrode material) to enhance material removal rate (MRR), tool wear rate (TWR), and surface roughness was achieved through Taguchi–Grey relational analysis. Upon analysis, it was determined that under the selected input conditions, 3 amperes current, 40% duty factor, and an extensively treated electrode had yielded the most optimized response. Following a confirmation test, a 0.6% enhancement in the predicted Grey relational grade was observed.</p></div>","PeriodicalId":502,"journal":{"name":"Bulletin of Materials Science","volume":"49 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147561226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surface functionalization techniques for improved additive manufacturing of aramids","authors":"Deepali Sanjay Kulkarni,&nbsp;Amol Indalkar,&nbsp;Shruti Gupta,&nbsp;Balasubramanian Kandasubramanian","doi":"10.1007/s12034-025-03535-x","DOIUrl":"10.1007/s12034-025-03535-x","url":null,"abstract":"<div><p>Aramid fibres serve as exceptional reinforcements in composite materials owing to their combination of high modulus, superior specific strength and low density. Their remarkable properties make them well-suited for additive manufacturing (AM) applications. However, their smooth, chemically inert surface limits fibre–matrix bonding. Surface modifications enhance surface roughness and chemical activity, improving adhesion and composite performance. Unlike conventional methods, AM offers precise control over material distribution, fibre alignment and complex geometries, enabling lightweight, strong structures. Aramid fibre-reinforced polymers produced through AM show enhanced tensile strength, superior impact resistance and enhanced thermal stability, rendering them highly advantageous for aerospace, automotive and defence industries. Fused filament fabrication and selective laser sintering, which are the recent advancements in AM technologies, have improved fibre dispersion and orientation in both thermoplastic and thermosetting matrices, while reducing material waste and supporting sustainability. Despite these benefits, challenges like fibre breakage, anisotropic mechanical properties and poor interfacial adhesion persist. Future research should focus on printing parameter optimization, developing novel fibre–polymer compatibilization techniques, and exploring hybrid reinforcements to further improve AM-fabricated aramid composites. As AM evolves, it holds significant potential to transform composite manufacturing through enhanced design flexibility, efficiency and mechanical performance.</p><h3>Graphical abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":502,"journal":{"name":"Bulletin of Materials Science","volume":"49 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147560320","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Achieving single-phase pentaniobium trisilicide using mechanically activated self-propagating high-temperature synthesis","authors":"Olga A Shkoda","doi":"10.1007/s12034-026-03577-9","DOIUrl":"10.1007/s12034-026-03577-9","url":null,"abstract":"<div><p>The effect of mechanical activation of silicon and niobium powders of stoichiometric composition for pentaniobium trisilicide was investigated for the synthesis of single-phase pentaniobium trisilicide via self-propagating high-temperature synthesis. The conditions for mechanical activation, the average agglomerate size, and the temperature characteristics of the subsequent thermal explosion were determined. It was established that the synthesis proceeds in a solid-state regime, yielding a single-phase product.</p></div>","PeriodicalId":502,"journal":{"name":"Bulletin of Materials Science","volume":"49 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147560617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Engineering photoresponsive chitosan-azo-o-vanillin Schiff bases with enhanced antimicrobial and biocompatible properties","authors":"Akash Siotey,&nbsp;Unnati Singhania,&nbsp;Purnima Jain,&nbsp;Ejaj K. Pathan,&nbsp;Swapnil L. Sonawane","doi":"10.1007/s12034-026-03569-9","DOIUrl":"10.1007/s12034-026-03569-9","url":null,"abstract":"<div><p>Chitosan–Schiff base derivatives have emerged as promising antimicrobial agents due to their tunable physicochemical and surface properties. To yield Schiff base derivatives, chitosan can be protonated and, subsequently, functionalized with molecules containing an aldehyde group. In the present study, we synthesized azo<i>-o-</i>vanillin Schiff base derivatives of low-molecular-weight chitosan, with varying the amount of azo<i>-o-</i>vanillin loading. The successful formation of Schiff base linkages was confirmed with the help of FTIR and CP-MAS (solid state) ¹³C NMR spectra. The thermal and morphological features of the materials were investigated using thermogravimetric analysis, derivative thermogravimetry, differential scanning calorimetry, scanning electron microscopy, and X-ray diffraction analyses. SEM revealed rough, uneven, and helical surface morphologies. The azo<i>-o-</i>vanillin functionalized chitosan derivatives also exhibited enhanced photoresponsive behavior. Increasing azo<i>-o-</i>vanillin content into the chitosan leads to the formation of imine linkages resulting in improved thermal stability and antimicrobial properties of the chitosan-azo<i>-o-</i>vanillin Schiff bases. The antimicrobial activity of the chitosan Schiff bases showed stronger inhibition of human pathogenic fungi and bacteria than clinically used antifungal and antibacterial drugs. The antibacterial and antifungal activities of chitosan-azo–Schiff base compounds were found to be associated with their ability to interfere with the cell membrane and thereby produce reactive oxygen species, leading to cell death. All the derivatives showed negligible cytotoxicity and hemolytic activity, confirming their biocompatibility. These findings highlight the potential of low-molecular-weight chitosan-azo<i>-o-</i>vanillin Schiff base materials in biomedical applications.</p><h3>Graphical abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":502,"journal":{"name":"Bulletin of Materials Science","volume":"49 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147560072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detailed analysis of the effect of dysprosium(III) oxide on the mechanical and gamma-ray shielding properties of borate-based glasses","authors":"Mohamed S. I. Koubisy,&nbsp;Karem Mahmoud,&nbsp;Ahmed M Henaish,&nbsp;M. I Sayyed,&nbsp;Yasser A. M. Ismail","doi":"10.1007/s12034-026-03571-1","DOIUrl":"10.1007/s12034-026-03571-1","url":null,"abstract":"<div><p>We evaluated the role of dysprosium(III) oxide (Dy₂O₃) on the thermal, mechanical, and gamma-ray shielding properties of a lead-borate-based glass system. A series of six glass samples were fabricated according to the chemical formula 20ZnO + (40-z)B₂O₃ + 40PbO + zDy₂O₃, where z = 0, 1, 2, 3, 4, and 5 wt%, using the melt-quenching method. The thermal properties of the fabricated glasses were measured using a Shimadzu DTG-60H thermal analyzer, with temperatures ranging from 25 to 90°C. Additionally, Fourier-transform infrared (FTIR) analysis was performed using a JASCO FTIR-430 spectrophotometer. The mechanical properties of the investigated glasses were evaluated both analytically and empirically based on the Makishima–Mackenzie model. The elastic moduli and ultrasonic velocities were found to increase with the rising Dy₂O₃ content in the investigated glasses. The Young’s, bulk, shear, and longitudinal moduli exhibited enhancement due to the partial substitution of B–O bonds by stronger Dy–O bonds. Furthermore, the gamma-ray shielding properties showed a slight improvement with the substitution of B₂O₃ by Dy₂O₃. The highest mass attenuation coefficient was achieved at 0.015 MeV, increasing from 55.045 to 59.415 cm² g⁻¹ as the Dy₂O₃ content rose from 0 to 5 wt%.</p></div>","PeriodicalId":502,"journal":{"name":"Bulletin of Materials Science","volume":"49 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147560070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigations of the tetragonal phase in NaGeI2F-based mixed perovskite: a first-principles approach","authors":"Hameed T Abdulla,&nbsp;Bewar M Ahmad,&nbsp;Mohammed Noor S Rammoo,&nbsp;Nawzad A Abdulkareem","doi":"10.1007/s12034-026-03546-2","DOIUrl":"10.1007/s12034-026-03546-2","url":null,"abstract":"<div><p>In this study, density functional theory (DFT) was employed to investigate the structural, optoelectronic and thermodynamic properties of a novel mixed tetragonal phase structure of NaGeI₂F perovskite. According to the electronic properties, the investigated band structure reveals that the structure offers a direct bandgap of ~1.49 eV, consistent with the beginning point of absorption observed in its optical properties. This alignment between computational results and optical analysis emphasizes the reliability of the results, particularly in the absence of theoretical or experimental data for comparison with this novel compound. The optical properties were further analysed, including the real part of the dielectric constant, refractive index, reflectivity, loss functions, extinction coefficient and absorption coefficient, as functions of energy and wavelength. In addition, mechanical property assessments indicated that the bulk modulus (<i>B</i>) of NaGeI₂F increases under applied pressure, suggesting enhanced structural stability at elevated temperatures and compressive conditions. Thermodynamic evaluations, including the calculated Gibbs free energy (<i>G</i>) and entropy (<i>S</i>), provided further insights into the material’s behaviour across varying pressure and temperature regimes. This study highlights the potential of NaGeI₂F for technological applications, owing to its high stability and dependable performance under diverse environmental conditions.</p></div>","PeriodicalId":502,"journal":{"name":"Bulletin of Materials Science","volume":"49 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147559394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}