Journal of Materials Science & Technology最新文献

{"title":"Ultrahigh thermal conductivity and photothermal conversion in interface-optimized bacterial cellulose/boron nitride nanosheets/MXene composites","authors":"Xinyue Liu, Zhongguo Zhao, Xin Xie, Kaiyuan Wang, Wenhu Li, Chouxuan Wang, Rong Xue, Lei Wang","doi":"10.1016/j.jmst.2025.06.010","DOIUrl":"https://doi.org/10.1016/j.jmst.2025.06.010","url":null,"abstract":"Polymer-based thermal conductive composites (PTCs) are crucial for managing heat in microelectronics, yet the impact of filler–filler interfacial thermal resistance (ITR) on their thermal performance remains unclear despite efforts to optimize the filler–matrix interfaces. In this study, the creation of continuous thermal conductive networks with enhanced filler–filler interface contact was achieved in bacterial cellulose/boron nitride nanosheets/MXene composites (BC/BNNS/MXene) by the in-situ coating of silver nanoparticles on the surface of boron nitride nanosheets (Ag@BNNS). The homogeneously dispersed and well-exfoliated BNNS are bridged to each other via the Ag located at the surface of BNNS and a 3D thermal conductive network is formed with solid Ag junctions lying in among. The resulting 3D “branch-leaf” structure significantly enhances thermal conductivity to 18.5 W m<ce:sup loc=\"post\">−1</ce:sup> K<ce:sup loc=\"post\">−1</ce:sup> at 30 wt% Ag@BNNS filler loading, and was demonstrated by first-principles simulations, proving that the merged Ag was used as a thermal transport joint to reduce thermal contact resistance within the 3D BNNS and MXene network. Utilizing the MBAg30 composite film as a thermal interface material has been shown to effectively lower the operating temperature of smartphones, reducing it from 33.4°C to 29.0°C. The film also demonstrates efficient photothermal conversion, with a surface temperature of 83.6°C under 100 mW cm<ce:sup loc=\"post\">−2</ce:sup> light intensity and a photothermal conversion efficiency of 96.3 %. It demonstrates good stability after seven cycles and can increase ice melting rates in practical applications like agricultural greenhouses and solar heating. The present strategy provides an effective route for developing high-performance PTCs.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"24 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144515364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In-situ synchrotron high-speed X-ray imaging of balling behavior and pore evolution during laser powder bed fusion under overhang condition","authors":"Liang Zhao, Wenquan Lu, Zhun Su, Jianguo Li, Qiaodan Hu","doi":"10.1016/j.jmst.2025.05.043","DOIUrl":"https://doi.org/10.1016/j.jmst.2025.05.043","url":null,"abstract":"The formation and evolution of defects during laser powder bed fusion (LPBF) have been extensively investigated to enhance the performance of manufactured parts. However, there remains a lack of fundamental understanding regarding defect formation and elimination mechanisms during LPBF under overhang conditions. In this study, we employed a synchrotron high-speed X-ray imaging technique to track the behavior of powder spheroidization, pore formation, and escape, as well as the impact of pore growth on molten pool surface stability during overhang build using mechanically mixed Fe-Cu powder. Our findings revealed that the notable difference in the melting degree of the powder bed is the primary driving force for balling. The coalescence of spherical droplets and the continuous wetting at the melt pool boundary with the powder bed can promote melt track growth. Additionally, numerous pores emerge within the molten pool due to the “liquid phase sintering (LPS) mechanism”. To describe pore escape behavior accurately, we established and validated a pore bursting model. Furthermore, adjacent pores can interfere with each other thereby restricting pore escape and diminishing molten pool surface stability. Overall, our results elucidate defect formation mechanisms while providing guidance for mitigating spheroidization and pores in LPBF.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"18 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144515432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"β-spodumene-doped lithium disilicate glass-ceramics via additive manufacturing for dental applications","authors":"Jianfeng Ma, Xin Zhou, Zenqi Ye, Xian Tong, Zhaoping Chen, Qianshu Xia, Tianran Wang, Yangshuai Jin, Yuncang Li, Jixing Lin, Zhe Zhao, Cuie Wen, Li Zhu","doi":"10.1016/j.jmst.2025.04.082","DOIUrl":"https://doi.org/10.1016/j.jmst.2025.04.082","url":null,"abstract":"Lithium disilicate glass-ceramics (LDGCs) are widely employed in dental aesthetic restorations; however, their application is constrained by insufficient fracture toughness and the inefficiencies inherent in conventional milling processes. This study investigated the additive manufacturing of LDGCs doped with β-spodumene to address these limitations. LDGCs doped with 0, 2.5, 5, 10, and 20 wt% β-spodumene were prepared via additive manufacturing followed by heat treatments, and their thermal behavior, density, phase composition, microstructure, mechanical properties, and molding accuracy were evaluated. The results indicate that as the doping level of β-spodumene increased, the porosity, crystallinity, strength, and toughness initially improved and then decreased, with the most significant enhancement observed at 2.5 wt%. The size of lithium disilicate crystals decreased as the doping of β-spodumene increased. Notably, the 2.5 wt% doped composites demonstrated a toughness of 3.4±0.2 MPa m^1/2, attributed to the secondary phase toughening mechanism of β-spodumene. Additionally, these β-spodumene-doped LDGCs exhibit excellent molding accuracy. These findings suggest that β-spodumene-doped LDGCs possess good mechanical properties and machinability, showing promising potential for dental restorative applications.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"82 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144488422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of hot oscillating pressing on microstructure and mechanical properties of FGH4095 nickel-based superalloy","authors":"Jingwei Chen, Chuncheng Lu, Enhui Wang, Tao Yang, Chunyu Guo, Yan Fan, Yingnan Shi, Jinhui Wang, Xinmei Hou","doi":"10.1016/j.jmst.2025.05.040","DOIUrl":"https://doi.org/10.1016/j.jmst.2025.05.040","url":null,"abstract":"The preparation process is of great importance to the densification of nickel-based powder metallurgy superalloys. In this work, a novel approach of hot oscillating pressing (HOP) has been adopted to prepare dense FGH4095 superalloy (FGH4095). For comparison, the hot pressing (HP) process is also applied. MSC Marc is employed to optimize the sintering parameters of the HOP process. Benefited from the enhanced grain boundary sliding and plastic deformation resulting from the oscillation pressure, FGH4095 possesses a higher precipitation proportion of secondary γ′ phase with lower content of thermally induced porosity (TIP) and previous particle boundaries (PPBs) precipitated phases. Therefore, the room-temperature yield strength and ultimate tensile strength reach up to 1153 and 1433 MPa with an elongation of 10.46%. A ductile damage model has been established to further investigate the mechanical properties of FGH4095 prepared by the HOP process. Based on the ABAQUS simulation, the tensile behavior of FGH4095 is predicted.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"17 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144479490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intensive analysis of anti-corrosion properties of cold rolled steel in trichloroacetic acid solution by camellia oleifera shells derived carbon dots","authors":"Min Tang, Shuduan Deng, Yujie Qiang, Dandan Shao, Xianghong Li","doi":"10.1016/j.jmst.2025.05.042","DOIUrl":"https://doi.org/10.1016/j.jmst.2025.05.042","url":null,"abstract":"Carbon dot inhibitors (UTCDs, HSCDs) are successfully prepared for the first time by ultrasonic treatment and hydrothermal synthesis from <em>Camellia oleifera</em> shells (COS), respectively. The fluorescence properties and structures of UTCDs and HSCDs, as well as their corrosion inhibition and adsorption mechanisms on cold rolled steel (CRS) in trichloroacetic acid (Cl₃CCOOH) solution, are investigated in depth. It is found that HSCDs exhibit stronger fluorescence and higher corrosion inhibition performance than UTCDs at a lower dose (300 mg L⁻¹, 91.6%). They possess amorphous carbon matrix, crystalline regions, surface functional groups, and active compounds. HSCDs have multiple protective mechanisms, including forming physical barriers, reducing oxides, and depleting C and O atoms in the corrosive medium. The enhancement of synthesis methods enables the mass production of HSCDs that effectively prevent corrosion.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"52 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144479491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 excellent strength-ductility synergy in orientation-heterostructured Mg-Y alloy via element segregation-assisted pinning of twin boundary","authors":"Yuliang Yang, Yuxin Liu, Zhufeng He, Ye Yuan, Lifang Sun, Shuang Jiang, Nan Jia","doi":"10.1016/j.jmst.2025.06.009","DOIUrl":"https://doi.org/10.1016/j.jmst.2025.06.009","url":null,"abstract":"The low strength, poor ductility, and limited cold formability of Magnesium (Mg) alloys have restricted their wide application as structural materials. The \"heterostructure\" design is a promising strategy for developing high-performance materials. In this work, four orientation-based heterostructured materials were fabricated by modulating bulk Mg-2.9Y (wt%) alloy to a single-pass strain of 10% for five complete triaxial cyclic compression (TCC) cycles along planes A, B, and C, followed by an additional compression on plane A. This process was combined with the subsequent annealing at 200°C for 1 h, leading to the hard-oriented 10%-5 cycles and 10%-5 cycles-200°C/1 h materials together with the soft-oriented 10%-5 cycles+A and 10%-5 cycles+A-200°C/1 h materials. They were characterized by dense refined twins and fragmented grains embedded in coarse-grained matrix. Compared to the TCC-processed materials, the annealed materials showed more pronounced strengthening. The 10%-5 cycles+A-200°C/1 h material exhibited the optimal combination of strength and ductility, with the periodic segregation of Y atoms at dense twin boundaries strengthening the hard domains and increasing deformation incompatibility between the soft and hard domains. The geometrically necessary dislocations significantly accumulated at the twin boundaries, resulting in pronounced hetero-deformation induced (HDI) strengthening. At high strains, the pinning effect of Y atoms gradually weakened, and &lt;span&gt;&lt;span style=\"\"&gt;&lt;/span&gt;&lt;span data-mathml='&lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow is=\"true\"&gt;&lt;mo is=\"true\"&gt;{&lt;/mo&gt;&lt;mn is=\"true\"&gt;10&lt;/mn&gt;&lt;mover accent=\"true\" is=\"true\"&gt;&lt;mn is=\"true\"&gt;1&lt;/mn&gt;&lt;mo is=\"true\"&gt;&amp;#xAF;&lt;/mo&gt;&lt;/mover&gt;&lt;mn is=\"true\"&gt;2&lt;/mn&gt;&lt;mo is=\"true\"&gt;}&lt;/mo&gt;&lt;/mrow&gt;&lt;/math&gt;' role=\"presentation\" style=\"font-size: 90%; display: inline-block; position: relative;\" tabindex=\"0\"&gt;&lt;svg aria-hidden=\"true\" focusable=\"false\" height=\"2.779ex\" role=\"img\" style=\"vertical-align: -0.812ex;\" viewbox=\"0 -846.5 3073 1196.3\" width=\"7.137ex\" xmlns:xlink=\"http://www.w3.org/1999/xlink\"&gt;&lt;g fill=\"currentColor\" stroke=\"currentColor\" stroke-width=\"0\" transform=\"matrix(1 0 0 -1 0 0)\"&gt;&lt;g is=\"true\"&gt;&lt;use is=\"true\" xlink:href=\"#MJMAIN-7B\"&gt;&lt;/use&gt;&lt;g is=\"true\" transform=\"translate(500,0)\"&gt;&lt;use xlink:href=\"#MJMAIN-31\"&gt;&lt;/use&gt;&lt;use x=\"500\" xlink:href=\"#MJMAIN-30\" y=\"0\"&gt;&lt;/use&gt;&lt;/g&gt;&lt;g is=\"true\" transform=\"translate(1501,0)\"&gt;&lt;g is=\"true\" transform=\"translate(35,0)\"&gt;&lt;use xlink:href=\"#MJMAIN-31\"&gt;&lt;/use&gt;&lt;/g&gt;&lt;g is=\"true\" transform=\"translate(0,198)\"&gt;&lt;use x=\"-70\" xlink:href=\"#MJMAIN-AF\" y=\"0\"&gt;&lt;/use&gt;&lt;use x=\"70\" xlink:href=\"#MJMAIN-AF\" y=\"0\"&gt;&lt;/use&gt;&lt;/g&gt;&lt;/g&gt;&lt;g is=\"true\" transform=\"translate(2072,0)\"&gt;&lt;use xlink:href=\"#MJMAIN-32\"&gt;&lt;/use&gt;&lt;/g&gt;&lt;use is=\"true\" x=\"2572\" xlink:href=\"#MJMAIN-7D\" y=\"0\"&gt;&lt;/use&gt;&lt;/g&gt;&lt;/g&gt;&lt;/svg&gt;&lt;span role=\"presentation\"&gt;&lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow is=\"true\"&gt;&lt;mo is=\"true\"&gt;","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"26 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144488358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Super-sensitive near-infrared organic photoelectric synaptic transistors based on sandwich-structured active layer","authors":"Hongyan Yu, Jingchun Sun, Xiaoli Zhao, Ning He, Guodong Zhao, Jiayi Zou, Yanping Ni, Chuang Xue, Jing Sun, Junru Zhang, Guoqiang Ren, Pengbo Xi, Cong Zhang, Yijun Shi, Yanhong Tong, Qingxin Tang, Yichun Liu","doi":"10.1016/j.jmst.2025.05.041","DOIUrl":"https://doi.org/10.1016/j.jmst.2025.05.041","url":null,"abstract":"High-sensitivity near-infrared organic photoelectric synaptic transistors present promising opportunities for developing machine-intelligent vision applications. However, the low sensitivity of organic photoelectric synaptic transistors remains a critical challenge, hindering their practical application. Although few approaches have attempted to address this issue, the short diffusion distance of photogenerated excitons limits the dissociation efficiency of excitons. Here, we present a super-sensitive near-infrared photoelectric synaptic transistor based on a sandwich structure photosensitive active layer and realize double-channel synergistic modulation. The devices have multiple functionalities that imitate the human visual system and achieve extremely high photoelectric sensitivity (∼10⁶) under near-infrared illumination (0.22 mW/cm²). The method of realizing a double-channel modulator with a sandwich structure can be applied to other organic polymer semiconductor materials to realize super-sensitive photoelectric synapses. This method paves the way for the invention of super-sensitive near-infrared neuromorphic imaging systems, which have enormous promise for artificial intelligence and intelligent night vision.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"38 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144479492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microstructures, mechanical properties and deformation mechanism of heterogeneous metal materials: A review","authors":"Shuaishuai Liu, Guangsheng Huang, Manoj Gupta, Bin Jiang, Fusheng Pan","doi":"10.1016/j.jmst.2025.03.109","DOIUrl":"https://doi.org/10.1016/j.jmst.2025.03.109","url":null,"abstract":"In recent years, a new type of fast emerging heterostructure materials (HSMs) has emerged in the field of metal materials. This material is composed of soft and hard regions with significant strength differences due to the heterogeneity of microstructure, crystal structure and composition. It can effectively break the inverted relationship between strength and ductility of traditional homogeneous materials, which mainly depends on the synergistic strengthening effect: hetero-deformation induced (HDI) strengthening and hardening. This paper adequately reviewed the heterogeneous deformation fundamentals, the microstructure characteristics and mechanical properties of various HSMs prepared by different processing methods. Meanwhile, we assess the mechanical behavior and influencing factors of the synergistic strengthening effect from the perspective of microscopic strain/stress, damage mechanism and key heterostructured parameters. In addition, the numerical simulations of HSMs are systematically revealed, which offers theoretical guidance for their quantitative design with the best mechanical properties. This paper aims to construct the relationships among the heterostructures, microscopic deformation mechanisms and macroscopic mechanical properties, provide a valuable reference for the optimal heterostructures, and explore crucial scientific issues that warrant further investigation.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"56 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144479489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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-target nanocomposites for Alzheimer’s treatment via microenvironment modulation and β-amyloid plaque clearance","authors":"Tongtong Hou, Dan Nie, Minling Ding, Chaoli Wang, Kun Mei, Xuanzhao Lu, Xin Wang, Selene Tang, Hong Wu, Ping Guan, Wenlei Zhu, Xiaoling Hu","doi":"10.1016/j.jmst.2025.04.081","DOIUrl":"https://doi.org/10.1016/j.jmst.2025.04.081","url":null,"abstract":"Simultaneously addressing Aβ₄₂ aggregation and oxidative stress within the Alzheimer's disease (AD) microenvironment has emerged as a promising therapeutic strategy for countering the complex pathogenesis of AD. In this study, we developed a multifunctional nanocomposite (GQDs@MPN) with reactive oxygen species scavenging properties. This nanocomposite consists of graphene quantum dots encapsulated within a metal-polyphenol network (GQDs@MPN) formed by physiological Co (II)-coordinated epigallocatechin gallate (EGCG). GQDs@MPN effectively modulates the AD microenvironment by inhibiting Aβ₄₂ amyloidosis, attenuating oxidative stress, and regulating microglial activity. In vivo experiments demonstrated that GQDs@MPN, capable of crossing the blood-brain barrier (BBB), significantly reduced Aβ₄₂ deposition in APP/PS1 mice. Additionally, GQDs@MPN could exert its anti-inflammatory function by scavenging intracellular ROS and regulating the transformation of microglia from M1 phenotype to M2 phenotype, thus alleviating neuroinflammation. The underlying molecular mechanism is the up-regulation of nuclear factor-erythroid 2-related factor 2 (Nrf2) to clear ROS and subsequently inhibit the nuclear factor κB (NF-κB) signaling pathway. GQDs@MPN also effectively alleviated cognitive impairment and exhibited favorable biocompatibility in APP/PS1 mice. These findings suggest that GQDs@MPN is a promising candidate for multi-targeted AD therapy. We propose that such multifunctional nanocomposites could offer new avenues for developing novel AD inhibitors.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"27 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144371081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unravelling the limit of the coercivity enhancement in PrAl grain boundary diffusion processed Nd‒La‒Ce‒Fe‒B magnets","authors":"Wang Chen, Hansheng Chen, Jiaying Jin, Liang Zhou, Mengfan Bu, Haoruo Zhou, Mi Yan, Simon P. Ringer","doi":"10.1016/j.jmst.2025.05.039","DOIUrl":"https://doi.org/10.1016/j.jmst.2025.05.039","url":null,"abstract":"The grain boundary diffusion (GBD) process is widely used to enhance the coercivity of Nd‒Fe‒B sintered magnets, representing a critical materials technology for advancing the electrification revolution. However, it is well known that the enhancement in coercivity achievable through the GBD process appears to reach a limit. To overcome this limitation, it is essential to thoroughly understand the formation of the magnetically hardening matrix shells and the evolution of the grain boundary (GB) phases along the diffusion path. Here we present the microstructural and magnetic evolution of the Pr-Al-rich matrix shells and the GB phases along the diffusion path in the Pr₈₀Al₂₀ GBD processed Nd‒La‒Ce‒Fe‒B magnets. Firstly, the Pr/total rare earth (TRE) ratio remains relatively constant in the Pr-Al-rich matrix shells from the magnet surface to an interior diffusion depth of ∼500 µm. The consistent Pr/TRE ratio identified within the matrix shells means that there is not a sustained increase in the nucleation field near the RE₂Fe₁₄B matrix grain/GB interface. Secondly, from the magnet surface to an interior diffusion depth of ∼500 µm, the antiferromagnetic high-Al δ-type RE‒Fe‒Al phase at the GBs transforms to a ferromagnetic low-Al μ-type or amorphous RE‒Fe‒Al phase. The predominance of the ferromagnetic low-Al μ-type or amorphous RE‒Fe‒Al phase beyond this diffusion depth implies that, apart from this sub-surface region, there is a lack of magnetic isolation of the adjacent ferromagnetic RE₂Fe₁₄B matrix grains through most of the bulk magnet. These factors jointly contribute to constraining or limiting the coercivity enhancement. We discuss how the microstructural origins of the limits to the coercivity enhancement in the GBD processed magnets found here can enable future design approaches for producing thicker Nd‒La‒Ce‒Fe‒B magnets with higher coercivity.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"45 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144371082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}