Materials Characterization最新文献

{"title":"Influence of residual segregation on γ’ precipitate and creep performance in novel nickel-based single-crystal superalloy","authors":"Abbas Jafri ,&nbsp;Zhaoyang Liang ,&nbsp;Zihao Tan ,&nbsp;Xipeng Tao ,&nbsp;Yanfei Liu ,&nbsp;Xinguang Wang ,&nbsp;Chuanyong Cui ,&nbsp;Jinguo Li ,&nbsp;Yizhou Zhou ,&nbsp;Xiaofeng Sun","doi":"10.1016/j.matchar.2026.116198","DOIUrl":"10.1016/j.matchar.2026.116198","url":null,"abstract":"<div><div>A series of solution heat treatment (SHT) processes was applied to investigate the creep behaviour at 1140 °C / 137 MPa of a novel nickel-based single-crystal superalloy. The γ/γ’ microstructure, including the γ’ size and volume fraction, was compared after each SHT. The SEM results reveal that a γ’ size gradient emerges between interdendritic and dendritic regions (DR), depending on the SHT process, as a result of remaining segregation of elements. WDS-EPMA quantification of residual segregation validated the microstructure differences observed via SEM, emphasising the impact of SHT on phase distribution. The creep response at ultra-high temperature, low stress was found to be correlated with the dimensions of the γ’ precipitates. The specimen featuring the smallest γ’ size in DR manifested a remarkable 67% increase in creep life compared to those with larger γ’ size. Post-creep microstructure analysis revealed that fine and highly uniform raft formation is attributed to the robust strengthening effect originating from small-size γ’ precipitates. These precipitates also facilitate a more equitable distribution of refractory elements, thereby reducing the propensity for the nucleation of topologically closed-packed phases. The underlying mechanisms for the enhanced creep resistance properties have been discussed.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"234 ","pages":"Article 116198"},"PeriodicalIF":5.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 recrystallization on plastic deformation of LPBF-Inconel 718 superalloy: The role of annealing twins","authors":"Dongqing Jia,&nbsp;Xiaopeng Cheng,&nbsp;Junxia Lu","doi":"10.1016/j.matchar.2026.116199","DOIUrl":"10.1016/j.matchar.2026.116199","url":null,"abstract":"<div><div>Laser powder bed fused (L-PBFed) Inconel 718 alloy shows anisotropic microstructure and mechanical properties. Recrystallization offers an effective method to enhance the microstructural homogeneity, thereby improving the mechanical properties. In this study, two heat treatments (1020-HSA and 1100-HSA) were applied to obtain samples with different degrees of recrystallization, and their deformation behaviors were investigated by using in-situ electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM) analyses. The results showed that recrystallization by heat treatment effectively eliminated cellular subgrains and decreased dislocation density. Meanwhile, recrystallization also promotes the formation of high-density annealing twins. These twins acted as barriers and storage sites for dislocations, which enhanced strain-hardening and deformation compatibility. Moreover, twin boundaries facilitated dislocation transmission and could transform into random high angle grain boundaries, which promoted uniform plastic deformation. Compared with the unrecrystallized specimen (1020-HSA), the 1100-HSA specimen exhibited improved ductility and stable strength, which achieved a favorable strength–ductility synergy. This study elucidated the underlying mechanisms by which recrystallization coordinated plastic deformation, guiding the design of heat treatment in L-PBFed Inconel 718.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"234 ","pages":"Article 116199"},"PeriodicalIF":5.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microstructural evolution and recrystallization mechanisms in a Cu-Ni-Co-Si alloy subjected to multi-step drawing and aging","authors":"Longjian Li ,&nbsp;Kai Zhao ,&nbsp;Hongrui Yu ,&nbsp;Gaojie Liu ,&nbsp;Zeyuan Chen ,&nbsp;Enlang Feng ,&nbsp;Huijun Kang ,&nbsp;Jinchuan Jie ,&nbsp;Zongning Chen ,&nbsp;Enyu Guo ,&nbsp;Tongmin Wang","doi":"10.1016/j.matchar.2026.116202","DOIUrl":"10.1016/j.matchar.2026.116202","url":null,"abstract":"<div><div>The synergistic optimization of strength and electrical conductivity continues to pose a considerable challenge in the development of precipitation-strengthened copper alloys, particularly in Cu-Ni-Co-Si systems, where the interactions between deformation and aging processes remain not yet fully understood. In this work, a multi-step cold-drawing strategy incorporating intermediate aging was designed to regulate recrystallization and precipitation behavior of a Cu-Ni-Co-Si-Mg-Ti alloy. Cold drawing induced a high density of dislocations and a pronounced fiber texture, which provided abundant heterogeneous nucleation sites for subsequent precipitate formation. Compared with conventional single-step drawing, the multi-step drawing process effectively inhibited recrystallization during aging, maintained subgrain stability, and retained a high dislocation density. This stabilized deformation framework promoted the uniform precipitation of nanoscale δ-(Ni, Co)₂Si particles and enhanced interactions between precipitates and dislocations, thereby improving both precipitation and dislocation strengthening. Concurrently, the progressive depletion of solute during aging decreased electron scattering, promoting a rapid recovery of electrical conductivity. Consequently, the alloy subjected to the optimized multi-step drawing and aging process achieved an outstanding combination of properties, including a yield strength of 905.5 MPa, an ultimate tensile strength of 977.1 MPa, and an electrical conductivity of 49.1% IACS. Quantitative analysis indicated that precipitation and dislocation strengthening contributed collectively to over 80% of the yield strength. These findings demonstrate that the synergistic regulation of recrystallization and precipitation through multi-step drawing and aging offers an effective and scalable strategy for the development of high-performance copper wire materials.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"234 ","pages":"Article 116202"},"PeriodicalIF":5.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Emergence of hierarchical textural pattern in a Fe-rich FeMnNiCr high-entropy alloy: Identification of Goss texture","authors":"Vahid Yousefi Mehr ,&nbsp;Mohammad Reza Toroghinejad ,&nbsp;Yabo Fu ,&nbsp;Mahshid Kharaziha ,&nbsp;Raouf Rahimzadeh","doi":"10.1016/j.matchar.2026.116189","DOIUrl":"10.1016/j.matchar.2026.116189","url":null,"abstract":"<div><div>The evolution of texture has recently attracted interest because of its capacity to affect the metallurgical aspects of high-entropy alloys. Among different components, Goss texture is notable for its uniqueness but remains poorly understood. This study examines Goss development in a multicomponent Fe-rich FeMnNiCr alloy, focusing on the microstructure and texture relationship. After manufacturing via vacuum induction remelting, the alloy undergoes primary rolling and heat treatment at 1000 °C for 1 h, followed by thickness reductions from 12.5% to 50% to encourage texture formation. Notably, after a 50% reduction in thickness, the primary recrystallization texture transformed into a noticeable Goss texture. The observed texture fibers in the rolled samples reflect complex deformation mechanisms, including intermediate textures. Microstructural features such as dislocations, shear bands, and twins highlight the complexity of texture. Also, a dislocation-assisted twin coupling and stress analysis mechanism explains Goss texture formation. In conclusion, the Fe-rich high entropy alloy with developing Goss texture could be promising for structural applications, especially where anisotropic properties are a concern.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"234 ","pages":"Article 116189"},"PeriodicalIF":5.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 post-weld heat treatment on microstructure and mechanical properties of dissimilar TRIP- and slip-assisted high-entropy alloy welds","authors":"Heechan Jung ,&nbsp;Chahee Jung ,&nbsp;Sangwon Lee ,&nbsp;Gunjick Lee ,&nbsp;Hadiseh Esmaeilpoor ,&nbsp;Jeoung Han Kim ,&nbsp;Seok Su Sohn","doi":"10.1016/j.matchar.2026.116209","DOIUrl":"10.1016/j.matchar.2026.116209","url":null,"abstract":"<div><div>Joining HEAs with fundamentally different deformation mechanisms enables the integration of complementary strain-hardening behaviors, while simultaneously introducing challenges related to mechanical mismatch across the weldment. Importantly, welding such dissimilar HEAs gives rise to inherent challenges arising from compositional and microstructural mismatches, for which laser beam welding (LBW), owing to its high precision and low heat input, is particularly suitable. This study investigates the microstructure and mechanical behavior of LBW joints between two precipitation-hardened high-entropy alloys (HEAs) exhibiting distinct deformation mechanisms of transformation-induced plasticity (TRIP) and dislocation slip. Since fusion welding introduces compositional heterogeneity and residual stresses that can deteriorate joint performance, post-weld heat treatment (PWHT) was applied to promote precipitation evolution and enhance mechanical compatibility across the weldment. Aging at 750 °C promotes the formation of transgranular L1₂ and intergranular B2 precipitates across both base metals and the weld zone, establishing a continuous gradient in precipitate density and composition. This microstructure reconciles hardness mismatch, increases the weld-zone strength, and enables sequential strain transfer from the TRIP base metal through the weld into the slip base metal. As a result, the PWHT joint achieves a yield strength of 781 MPa and elongation of 15.9%, corresponding to ∼50% higher yield strength and a threefold increase in ductility compared with the as-welded condition. These findings highlight the role of precipitation evolution in establishing mechanically gradient structures and demonstrate an effective strategy to reconcile strength and ductility in dissimilar HEA weldments.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"234 ","pages":"Article 116209"},"PeriodicalIF":5.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microstructure evolution and mechanical property improvement of Ti-542 alloy under cryorolling-based annealing designs","authors":"Jinguang Li ,&nbsp;Shengqi Feng ,&nbsp;Mi Zhou ,&nbsp;Tianshui Zhou ,&nbsp;Shidong Zhu ,&nbsp;Hui Zhao ,&nbsp;Lei Wang ,&nbsp;Zhiqiang Zhang","doi":"10.1016/j.matchar.2026.116217","DOIUrl":"10.1016/j.matchar.2026.116217","url":null,"abstract":"<div><div>The cryorolling at liquid nitrogen temperature and recrystallization annealing treatment (CRAT) has been applied on the Ti-542 metastable β titanium alloy, aiming to address the strength-plasticity inversion issue. The results show that CRAT can significantly modify the microstructure, not only by reducing the average grain size by nearly one order of magnitude, but also by creating a mixed-grain structure when annealing near the phase transformation temperature. The deformation mechanism during cryorolling is mainly governed by {332}〈113〉 twinning, and annealing at 770–780 °C can precisely balance the proportion between detwinning and grain refinement. The strength-plasticity matching of the alloy after CRAT has been remarkably enhanced, where the sample can exhibit a tensile strength of 1138.4 MPa (increased by 27% than the samples without CRAT) and a fracture elongation of 23.1%, overcoming the strength-plasticity trade-off limitation. The deformation behavior analysis by in situ High Energy X-Ray Diffraction (HEXRD) shows that the excellent performance of the alloy arises from the synergistic effects of the coarse-grain/fine-grain structure and advantage/random orientation distribution, which not only enhances the cooperative deformation characteristics but also improves the work hardening capacity. This research is expected to provide a theoretical basis and practical guidelines for the microstructure design and property control of new metastable β titanium alloys.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"234 ","pages":"Article 116217"},"PeriodicalIF":5.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Precipitation and recrystallization behavior of cold rolled CuTi alloy after aging in a wide range of temperature","authors":"Q.W. Li ,&nbsp;M. Jia ,&nbsp;W. Wang ,&nbsp;Y.Z. Tian","doi":"10.1016/j.matchar.2026.116150","DOIUrl":"10.1016/j.matchar.2026.116150","url":null,"abstract":"<div><div>The microstructural evolution and property changes of cold-rolled Cu-4 Ti alloy during aging treatments at temperatures ranging from 300 °C to 800 °C for 20 min were systematically investigated. At temperatures below 400 °C, spinodal decomposition dominated, forming coherent Ti-rich regions and resulting in a peak tensile strength of 1115 MPa. Aging at 500 °C led to peak electrical conductivity of 14.7% IACS and activated partial recrystallization, forming metastable <em>β'</em>-Cu₄Ti precipitates in deformed regions and equilibrium <em>β</em>-Cu₄Ti precipitates in recrystallized regions. Complete recrystallization occurred above 600 °C, improving ductility significantly and increasing the uniform elongation to 32% at 800 °C. The intense cold rolling enhanced discontinuous precipitation via strain energy provision and accelerated the mass transport. The variation of mechanical and electrical properties with aging temperature was discussed, and mechanisms for the precipitation and recrystallization were revealed. This work elucidates the interplay between precipitation, recrystallization, and properties, enabling microstructure and property optimization in Cu<img>Ti alloys.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"234 ","pages":"Article 116150"},"PeriodicalIF":5.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gradient transition and solution strengthening mechanisms in SiCf/SiC composites joints brazed with medium-entropy alloy filler","authors":"Yu Zhang ,&nbsp;Wei Guo ,&nbsp;Jiapeng Dong ,&nbsp;Han Mei ,&nbsp;Tianwei Shao ,&nbsp;Datao Xu ,&nbsp;Ying Zhu ,&nbsp;Hongqiang Zhang","doi":"10.1016/j.matchar.2026.116161","DOIUrl":"10.1016/j.matchar.2026.116161","url":null,"abstract":"<div><div>A Ti-Ni-Nb-Zr medium-entropy alloy filler was developed to achieve a uniform microstructure and effective stress transition in the SiC_f/SiC composites brazed joints. Composition gradients of Ti, Nb, and Ni across the asymmetric interface promoted the formation of a thermal-expansion transition structure, while the solid-solution strengthening contribution of Zr was clarified. A multiscale architecture integrating solution strengthening and stress transition was constructed, enabling synergistic enhancement through thermal-expansion mismatch mitigation and grain-scale stress accommodation. The gradient transition mechanism at the SiC_f/SiC composites asymmetric interface was elucidated by correlating NbC nucleation-growth-induced stress concentration, high-entropy solid solution effect in Ti-Ni-Nb-Zr, and the crystallographic matching between TiSi₂ and γ-(Ni, Cr, Fe) phases. Benefiting from the coupled strengthening mechanisms, the joint strength increased by nearly 300%, with fracture initiating in the interfacial reaction zone and exhibiting a cross-regional mixed mode. This work provides new mechanistic insight into interfacial design for carbon-based ceramic composites and establishes a scientific basis for the high-temperature brazing of advanced ceramic-metal systems.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"234 ","pages":"Article 116161"},"PeriodicalIF":5.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accurate segmentation of high-density dislocations in micrographs with DeepCrack model","authors":"Ruohan Shen ,&nbsp;Yujia Zhai ,&nbsp;Hongda Chen ,&nbsp;QinQin Shao ,&nbsp;Jia Liu","doi":"10.1016/j.matchar.2026.116206","DOIUrl":"10.1016/j.matchar.2026.116206","url":null,"abstract":"<div><div>Dislocations are fundamental defects in crystalline materials that critically influence mechanical properties and deformation mechanisms. Accurate segmentation of dislocation lines in micrographs is essential for quantitative microstructure analysis, yet it remains challenging due to complex contrast variations, high density, and morphological complexity. In this work, we adapt and retrain the DeepCrack model, a deep learning architecture originally designed for crack detection, to segment dislocations in experimental micrographs. Using a carefully annotated dataset of only 124 images acquired via scanning transmission electron microscopy and X-ray topography, which exhibit diverse dislocation morphologies and densities, the retrained model demonstrates strong generalization capability and accurate segmentation performance. It performs robustly even on highly challenging cases with extremely dense dislocation networks and significant image noise, albeit with a trade-off in output quality to avoid overfitting by shortening model training epochs. To overcome this limitation, a model recursion strategy was explored, which demonstrates potential for achieving top-tier recognition accuracy and high-quality binarized segmentation.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"234 ","pages":"Article 116206"},"PeriodicalIF":5.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reinforcement of boron carbide (B4C) ceramics with boron nitride nanotubes (BNNTs)","authors":"Heng Wang ,&nbsp;Yi Zeng ,&nbsp;Tianbin Zhu ,&nbsp;Yibiao Xu ,&nbsp;Lixia Fan ,&nbsp;Yawei Li ,&nbsp;Yajie Dai ,&nbsp;Fan Zhang","doi":"10.1016/j.matchar.2026.116195","DOIUrl":"10.1016/j.matchar.2026.116195","url":null,"abstract":"<div><div>Boron nitride nanotubes (BNNTs) were incorporated as a reinforcing additive into boron carbide (B₄C) ceramic matrices and consolidated <em>via</em> spark plasma sintering (SPS) at 1650–1800 °C. The resulting B₄C-BNNTs ceramic composites achieved a high relative density of 99.71 ± 0.12%, along with an optimal flexural strength of 702 ± 16 MPa, fracture toughness of 4.98 ± 0.13 MPa·m^1/2, and Vickers hardness of 35.3 ± 0.13 GPa—representing improvements of 226 MPa (47.47%), 1.21 MPa·m^1/2 (32.10%), and 2.0 GPa (6.01%) over monolithic B₄C, respectively. The enhanced mechanical performance is attributed to a combination of reinforcement mechanisms: (i) BNNTs-induced promotion of B₄C grain rearrangement, facilitated by the reduced densification temperature; (ii) <em>in-situ</em> formation of ZrB₂ and semi-coherent ZrB₂/B₄C interfaces; and (iii) crack bridging, deflection, and propagation resistance provided by BN and ZrB₂. This study elucidates the underlying reinforcement mechanisms in BNNTs-reinforced B₄C composites and provides a theoretical foundation for utilizing BN-based nanostructures to enhance the mechanical properties of B₄C ceramics.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"234 ","pages":"Article 116195"},"PeriodicalIF":5.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}