Journal of Magnetism and Magnetic Materials最新文献

{"title":"Crystallite structure and magnetic characteristics of iron oxide nanoparticles biomineralized by Shewanella spp. with different surface charge potentials","authors":"Saranath Parthasarathy,&nbsp;T.S. Chandra","doi":"10.1016/j.jmmm.2025.172814","DOIUrl":"10.1016/j.jmmm.2025.172814","url":null,"abstract":"<div><div><em>Shewanella</em> spp. are iron-reducing bacteria that exhibit different surface charge potentials depending on variations in their cell wall composition. It is postulated that such changes, which occur under different growth conditions, may influence the characteristics of nanomaterials synthesized by these bacteria. The surface charge potential and iron reduction profiles of different <em>Shewanella</em> spp. can thus be exploited to tune the properties of magnetic iron oxide nanoparticles (MNPs) for different applications. These aspects have not been investigated in depth. In this study, the structural, magnetic, and biological properties of MNPs mineralized by <em>Shewanella oneidensis</em> MR-1 and <em>Shewanella putrefaciens</em> CN-32 were characterized and compared. The products were analyzed using X-ray diffraction, electron microscopy, and dynamic light scattering to determine their crystalline structure, particle diameter, and size distribution, respectively. MNPs synthesized by <em>S. oneidensis</em> MR-1 had a more compact crystal structure than those produced by <em>S. putrefaciens</em> CN-32. Iron reduction under non-growth conditions resulted in a smaller particle size, more defined shape, and smoother surface compared to those under growth conditions. Magnetic properties measured using vibrating sample magnetometry indicated an incomplete superparamagnetic state for <em>S. putrefaciens</em> nanoparticles and a superparamagnetic state for <em>S. oneidensis</em> nanoparticles under non-growth conditions. Hence, resting conditions not only facilitate the sustainable synthesis of MNPs but also offer better control over particle crystallization. Cytotoxicity was absent under both conditions. This study contributes to the understanding of biologically synthesized MNPs and highlights the potential of <em>Shewanella</em> spp. as reliable sources for producing uniform and functional nanomaterials under environmentally benign conditions.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"616 ","pages":"Article 172814"},"PeriodicalIF":2.5,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magnetic particle dispersion in magnetorheological slurries for planarization enhancement","authors":"An-Jun Zheng,&nbsp;Chia-Chen Li","doi":"10.1016/j.jmmm.2025.172803","DOIUrl":"10.1016/j.jmmm.2025.172803","url":null,"abstract":"<div><div>This study investigates the application of an innovative magnetorheological (MR) slurry in chemical mechanical planarization (CMP), addressing challenges in precision, environmental sustainability, and adaptability to complex interconnect architectures faced by conventional CMP slurries. The MR slurry, composed of carbonyl iron particles (CI) and abrasive particles dispersed in an aqueous medium, achieves real-time control via magnetic field manipulation. Experimental results demonstrate that ammonium polyacrylic acid (PAA-NH₄) significantly improves the dispersion of both large and small CI particles, enhancing their alignment under an applied magnetic field. Rheological measurements, supported by finite element simulations, reveal that smaller, well-dispersed CI particles align more efficiently, forming closely packed and robust chain structures. This results in uniform magnetic brushes with improved coverage of the polishing surface, enabling a gentler, more efficient polishing process. Dispersed MR slurries achieve higher material removal rates (MRR) and better surface flatness, with smaller CI particles proving particularly effective due to their superior magnetization and stress application capabilities. These findings demonstrate the potential of MR slurries to deliver precise and efficient planarization in advanced applications.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"616 ","pages":"Article 172803"},"PeriodicalIF":2.5,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detection of carburization and defective weld in austenitic stainless steel using magneto-impedance arrayed sensor","authors":"Somnath Das ,&nbsp;Dev Kumar Mahato ,&nbsp;Ashis Kumar Panda","doi":"10.1016/j.jmmm.2025.172811","DOIUrl":"10.1016/j.jmmm.2025.172811","url":null,"abstract":"<div><div>The present investigation addresses an electromagnetic sensor comprising of an array of rapidly quenched amorphous microwires. Given the arrayed configuration, along with its low field sensitivity, the sensor has a promising scope because of its larger footprint for the assessment of industrial steel components. The research involves a novel approach to the design of an arrayed magneto-impedance sensor with such attributes. The low sensitivity of a single microwire towards feeble magnetic field was enhanced through a multi-wired arrayed magneto-impedance (MI) sensor. The arrayed microwire sensor output has been enhanced through Joule annealing of amorphous microwires. The potential scope of arrayed MI sensors for the detection of carburization in austenitic stainless steel and defective welds has been demonstrated. The low field sensitivity has been endorsed through COMSOL Multiphysics simulation studies.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"615 ","pages":"Article 172811"},"PeriodicalIF":2.5,"publicationDate":"2025-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143098417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The contribution of spin fluctuations to resistivity in B20 metals MnSi and MnGe","authors":"M.A. Anisimov ,&nbsp;A.V. Bogach ,&nbsp;S.V. Demishev ,&nbsp;N.A. Samarin ,&nbsp;A.V. Semeno ,&nbsp;A.V. Sidorov ,&nbsp;A.V. Tsvyashchenko","doi":"10.1016/j.jmmm.2025.172799","DOIUrl":"10.1016/j.jmmm.2025.172799","url":null,"abstract":"<div><div>Mn-based metallic helimagnets (MnSi and MnGe) were studied by detailed measurements of electrical resistivity at temperatures 2–300 K and magnetic fields up to 8.2 T. To interpret the data the procedure of ρ(<em>T</em>) analysis was applied. The approach presented here is based on River-Zlatic model [N. Rivier, and V. Zlatic, J. Phys. F: Met. Phys. <strong>2</strong>, L87 (1972)]. The decomposition performed allowed identifying along with electron–phonon component the additional one caused by the scattering of electrons on localized spin fluctuations (LSF). It was shown that the last contribution plays significant role not only in paramagnetic (PM) but also in magnetically ordered states of compounds under investigation. Spin fluctuation temperature was estimated as θ_lsf(MnSi) ≈ 120 K and θ_lsf(MnGe) ≈ 250–300 K. This model may be applied to the resistivity analysis in other <em>d</em>-metallic systems.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"615 ","pages":"Article 172799"},"PeriodicalIF":2.5,"publicationDate":"2025-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143098414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental investigation on surface finishing of CaF2 via core–shell composite magnetic particles","authors":"Shengjie Zhan ,&nbsp;Jianbing Meng ,&nbsp;Xiaojuan Dong ,&nbsp;Youquan Tang ,&nbsp;Ertuan Zhao ,&nbsp;Zexu Zheng ,&nbsp;Yuewu Gao","doi":"10.1016/j.jmmm.2025.172810","DOIUrl":"10.1016/j.jmmm.2025.172810","url":null,"abstract":"<div><div>The surface precision of CaF₂ polished via magnetic abrasive finishing (MAF) mainly depend on the magnetic abrasive powder. A kind of core–shell structured magnetic abrasive with a hard Fe/Al intermetallic shell was prepared by in-situ alloy-hardening the surface of spherical carbonyl iron powders. The reaction temperature and time was proposed. The features of the prepared magnetic abrasive, including morphology, compositional and crystalline properties was characterized. The results of preparation and polishing experiments indicate that the prepared magnetic abrasive is composed of a carbonyl iron powder core and FeAl, Fe₃Al, Fe_0.4Al_0.6 metal compounds as the shell. The designed magnetic abrasive shows a good spherical shape and is coated with almost identical Fe/Al intermetallic compounds. The prepared magnetic abrasive achieved a refined roughness Ra to CaF₂ surface from initial 0.308 μm to 0.0246 μm, under the optimized combination of MAF process parameters.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"615 ","pages":"Article 172810"},"PeriodicalIF":2.5,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143098415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of silane coating and graphene oxide integration on the magnetothermal Behaviors of La1-xSrxMnO3 nanoparticles","authors":"Buse Sert ,&nbsp;Gul Kaya ,&nbsp;Sinem Cicek ,&nbsp;Ersan Harputlu ,&nbsp;Telem Şimşek ,&nbsp;Atakan Tekgül ,&nbsp;C. Gokhan Unlu ,&nbsp;Fatma Yurt ,&nbsp;Kasim Ocakoglu","doi":"10.1016/j.jmmm.2025.172808","DOIUrl":"10.1016/j.jmmm.2025.172808","url":null,"abstract":"<div><div>In this study, La_1-xSr_xMnO₃ (x = 0.27, 0.3, 0.33) magnetic nanoparticles (MNPs) were synthesized and then these nanoparticles synthesized in the core–shell structure were coated with silane for potential magnetic hyperthermia applications. In order to provide support material for the coated magnetic nanoparticles, silane-coated hybrid magnetic nanoparticles were obtained by producing graphene oxide (GO) nanoflakes. The structural and magnetic properties and magnetothermal properties of these structures were investigated. It was observed that the structure of the silane-coated magnetic nanoparticles remained intact and did not show any degradation compared to the uncoated materials. In addition, the highest saturation magnetization (<em>M_S</em>) value was observed in the sample doped with x = 0.30. This value indicated that the heating power would be higher than the other doped samples in the specific absorption ratio (SAR) measurements. In this context, the heating amount in the silane-coated samples showed a slight decrease compared to the uncoated samples. Despite the decrease in the SAR values ​​of the integrated samples by incorporating GO into the coated MNPs, it is anticipated that effective results will be obtained for practical applications with the advantage of increasing the thermal conductivity of GO.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"615 ","pages":"Article 172808"},"PeriodicalIF":2.5,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143098416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamics of current-driven spin waves in a confined track","authors":"Yunxi Jiang ,&nbsp;Xi Chen ,&nbsp;Chen Xuan ,&nbsp;Hem Raj Sharma ,&nbsp;Hao Yu","doi":"10.1016/j.jmmm.2025.172800","DOIUrl":"10.1016/j.jmmm.2025.172800","url":null,"abstract":"<div><div>This study investigates the generation, propagation, and decay of current-induced spin waves in a confined magnetic track through both theoretical analysis and numerical simulations. We derive an analytical expression for the spin wave dispersion and amplitude, establishing a linear relationship between the applied current density and the emitted wave frequency. The results reveal a deviation between the spin wave propagation direction and the current direction. As the spin waves decay, domain walls are generated in the system, with the number of domain walls being controlled by the current density and pulse duration. This research has promising applications in the field of spintronic devices, where controlled spin wave dynamics and domain wall creation could improve information processing and data storage. By tuning current-induced spin waves, these findings may support the development of magnetic memory elements, logic devices, and neuromorphic computing architectures that use domain walls for non-volatile memory and reconfigurable processing capabilities.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"615 ","pages":"Article 172800"},"PeriodicalIF":2.5,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143098418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evolution of the ground state of Yb ion in YbCu5-xSnx","authors":"F. Akbar ,&nbsp;I. Čurlík ,&nbsp;J. Kúdelčík ,&nbsp;M. Reiffers ,&nbsp;M. Giovannini","doi":"10.1016/j.jmmm.2025.172804","DOIUrl":"10.1016/j.jmmm.2025.172804","url":null,"abstract":"<div><div>Structural and magnetic studies have been carried out for the cubic YbCu_5-xSn_x system of the MgCu₄Sn-type, which exists in the solubility range 0.2 ≤ <em>x</em> ≤ 0.7. The magnetic properties of this system were compared with those of the analogous system YbCu_5-xIn_x (0.1 ≤ <em>x</em> ≤ 1.0). These two systems appear to share the same scenario of evolution from a localized trivalent state of the Yb atom for low values of <em>x</em>(<em>x</em> = 0.2) to valence transition state in a wide temperature range (T ∼ 40–80 K) for intermediate values of <em>x</em>(<em>x</em> = 0.6, 0.7). Specific heat measurements performed for one of these compositions, YbCu_4.4Sn_0.6, show an increase at low temperatures <em>T</em> &lt; 7 K most probably due to the presence of a high density of magnetic excitations.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"615 ","pages":"Article 172804"},"PeriodicalIF":2.5,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143098420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An investigation of tribological properties of magnetorheological grease with thermomagnetic coupling","authors":"Jiabao Pan ,&nbsp;Junjie Wang ,&nbsp;Jin Wang ,&nbsp;Guangxin Yang ,&nbsp;Xiaolei Wang","doi":"10.1016/j.jmmm.2025.172809","DOIUrl":"10.1016/j.jmmm.2025.172809","url":null,"abstract":"<div><div>Frictional and wear between components in magnetorheological devices critically influence on the operating stability, control accuracy, and service life. In particular, wear of the elastic seals may cause medium leakage and eventually lead to seal failure. This paper aims to investigate the tribological properties of magnetorheological grease with different thermomagnetic coupling conditions. First, a simulation analysis of the magnetic field distribution surrounding the friction subsurface is presented. Then, the tribological experiments are performed. Subsequently, experimental results and an ultra-depth digital microscope interactive system were combined to reveal thermomagnetic coupling lubrication mechanism. The experimental results indicate that different thermomagnetic coupling fields affect the tribological properties of magnetorheological grease and the magnetic field could compensate for the effect of temperature rise. The magnetic particles covered by the base oil will participate in the lubrication process. Moreover, the dispersed magnetic particles act as an intermediate layer and change the contact form in the friction area, thus reducing the friction coefficient. However, if the magnetic particles are agglomerated in large quantities, it may cause abrasive wear and increase the wear of the contact surface.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"615 ","pages":"Article 172809"},"PeriodicalIF":2.5,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143098421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Metrological determination of the soft magnetic properties of slot wedge material in electrical machines","authors":"Florian Kirchner ,&nbsp;Andreas Kremser","doi":"10.1016/j.jmmm.2025.172801","DOIUrl":"10.1016/j.jmmm.2025.172801","url":null,"abstract":"<div><div>Soft magnetic slot wedges as a composite of iron powder, resin and glass fiber are used to close the slots for the winding in electrical machines. Due to their magnetic properties, they influence the magnetic air gap field and the stray behavior of the electrical machine. By precisely dimensioning the material parameters, a reduction in the additional no-load losses and respectively an increase in the efficiency of the machines can be achieved. The determination and validation of the material properties are essential for the development of suitable materials and machine models. This document presents a measurement method for determining the magnetization curve and total losses, which in particular also enables the application to anisotropic materials as well as powders and pastes. The method was validated by comparative measurements using a standardized measurement method. After validation, various slot wedge materials were tested, and the results compared. It is shown that the magnetization curve and the total losses are depending on the filler share of soft magnetic particles. Using the specialized measurement setup, it was also found that some traditional soft magnetic slot wedge materials show anisotropic characteristics. In machine models with soft magnetic slot wedges, the investigated anisotropy as well as the total losses have not been considered in detail yet.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"615 ","pages":"Article 172801"},"PeriodicalIF":2.5,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}