International Journal of Plasticity最新文献

{"title":"Comparative analysis of processing technology on the deformation behavior of Al alloys studied by synchrotron X-ray diffraction and tomography","authors":"Weixiang He, Yuliang Zhao, Qiuyun Wei, Huan Liu, Baihui Gan, Dongfu Song, Zhenzhong Sun, Yanan Fu, Zhenhuang Su","doi":"10.1016/j.ijplas.2025.104261","DOIUrl":"https://doi.org/10.1016/j.ijplas.2025.104261","url":null,"abstract":"Recycled Al-Cu alloys deteriorated mechanical properties due to stress concentration caused by coarse Fe-rich intermetallic (Fe-rich phases). This study aims to comparative analysis of processing technology of ultrasonic melt processing (USMP) or/and Al-Ti-B on microstructure and deformation behavior of Al-Cu alloys. They were investigated using various microscopy technique, such as, scanning/transmission electron microscopy, electron backscattered diffraction, and synchrotron X-ray diffraction and tomography. Heat-treated Al-Cu alloys contained primary Al phase, Al₇Cu₂Fe, and Al₁₅(FeMn)₃(SiCu)₂ phases. The grain sizes of the 0.7FeU (0.7 wt% Fe + USMP) and 0.7FeUB (0.7 wt% Fe + USMP + Al-Ti-B) alloys decreased by 25.7% and 42.2%, respectively, compared to the 0.7FeB (0.7 wt% Fe + Al-Ti-B) alloy. This refinement led to significant improvements in mechanical properties: yield strength, tensile strength, and elongation increased by 18.7%, 53.7%, and 216.7% for 0.7FeUB. USMP resulted in a refined and compact morphology of the Fe-rich phases, reducing stress concentration. Under tensile testing, the fine grains in the 0.7FeUB alloy rotated in multiple directions, promoting uniform plastic deformation and stress distribution. The maximum lattice strain before fracture increased by 100% and 142% for the 0.7FeU and 0.7FeUB alloys, respectively, compared to the 0.7FeB alloy. USMP also enhanced Cu and Mg solubility, resulting in fine precipitates and increased dislocation density, strengthened alloys through solid solution, precipitation, and dislocation strengthening.","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"38 1","pages":""},"PeriodicalIF":9.8,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143020435","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":"Dislocation dissociation assisted formation mechanism of sigma phase and its impact on producing heterogeneous lamellar microstructure in CoCrV medium-entropy alloy","authors":"Luda Wang, Hai-Le Yan, Yudong Zhang, Benoit Beausir, Weimin Gan, Peltier Laurent, Nathalie Siredey-Schwaller, Claude Esling, Xiang Zhao, Liang Zuo","doi":"10.1016/j.ijplas.2025.104260","DOIUrl":"https://doi.org/10.1016/j.ijplas.2025.104260","url":null,"abstract":"Control of topologically close-packed sigma phase, meaning limiting its massive presence to avoid embrittlement but benefiting its refinement and strengthening effect, is of particular interest. In-depth knowledge of dislocation-associated formation mechanisms is needed but not well addressed. In this work, an FCC-phased Co_66.66Cr_16.67V_16.67 medium entropy alloy (MEA) with a propensity to form the sigma phase at non-equilibrium conditions was studied. The alloy was conventionally cold-rolled and heat-treated. The dislocation activity rooted formation mechanisms of the sigma phase were thoroughly characterized and evidenced by <em>in-situ</em> and <em>ex-situ</em> multi-scale diffraction techniques. It was revealed that nano-sized sigma particles enriched in Cr and V and depleted in Co were precipitated ultra-rapidly and uniquely during the heating process after the cold-rolling. The precipitation is spatially inhomogeneous, mainly in the severely deformed regions. The ultra-rapidity of the precipitation was achieved by the segregation of the Cr and V atoms via crystal defect-aided diffusion for composition change and by structure transformation via dislocation dissociation. The similarity of the atomic arrangement of the partial dislocations to that of the {001} sigma planes provides favorable structure transformation stimulus. In consequence, the orientations of the intensively activated dislocation slip planes dictated those of the sigma {001} planes via the FCC {111} to sigma {001} heredity, leading to the specific sigma texture. Owing to the spatially inhomogeneous precipitation, a heterogeneous lamellar microstructure was formed, composed of alternatively distributed fine dual-phased layers and coarse single-phased layers. This work provides comprehensive information on the dislocation-dissociation-assisted formation mechanism of sigma phase.","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"45 1","pages":""},"PeriodicalIF":9.8,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142990893","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":"Effects of elemental combination, stacking fault energy and temperature on the tensile deformation behavior of single crystals of quinary, quaternary and ternary equiatomic high- and medium-entropy alloys derived from the Cr-Mn-Fe-Co-Ni system","authors":"Le Li, Zhenghao Chen, Seiko Tei, Yusuke Matsuo, Ryosuke Chiba, Haruyuki Inui","doi":"10.1016/j.ijplas.2025.104257","DOIUrl":"https://doi.org/10.1016/j.ijplas.2025.104257","url":null,"abstract":"The effects of elemental combination, stacking fault energy (SFE) and temperature on the deformation behavior of single crystals of equiatomic high- and medium-entropy alloys (HEA and MEAs) with the face-centered cubic structure derived from the Cr-Mn-Fe-Co-Ni system have been investigated in tension at room temperature and 77 K. The SFE of these alloys varies from 83 mJ/m² to 14 mJ/m² and the efficiency in decreasing the SFE increases in the order of Cr&gt;Co&gt;&gt;Mn&gt;Fe. For all the HEA and MEAs investigated, the critical resolved shear stress for slip increases remarkably from room temperature to 77 K but does not exhibit any significant compression-tension asymmetry at both temperatures. Deformation in Stage I occurs in the form of Lüders band, the extent of which is temperature-independent but increases with the extent of solid-solution strengthening (SSS). The extent of yield drop increases also with the extent of SSS and with decreasing temperature. The work hardening rate of Stage II does not vary significantly from alloy to alloy but is slightly higher at 77 K than at room temperature. Deformation twinning occurs only in the Cr-Co-Ni MEA at room temperature, but at 77 K, it occurs in six HEA and MEAs with SFE≤32 mJ/m². Consequently, while at room temperature only the Cr-Co-Ni MEA exhibits remarkably superior tensile elongation, the tensile elongation at 77 K tends to increase with decreasing SFE in particular for those (with SFE≤32 mJ/m²) twin. The effects of twinning mechanisms (nucleation- and propagation-controlled twinning) on the twinning stress-SFE relationship are discussed.","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"13 1","pages":""},"PeriodicalIF":9.8,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142990892","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":"3D interface size effects on slip transfer in Ti/Nb nanolaminates","authors":"Nicolas Fuchs-Lynch, Mauricio De Leo, Pulkit Garg, Shuozhi Xu, Nathan A. Mara, Irene J. Beyerlein","doi":"10.1016/j.ijplas.2025.104246","DOIUrl":"https://doi.org/10.1016/j.ijplas.2025.104246","url":null,"abstract":"Two-phase nanolaminates are well-renowned for achieving extraordinarily high strengths but at the sacrifice of reduced toughness and strain to failure. Recently ”thick” interfaces, or so called 3D interfaces, in Cu/Nb nanolaminates were experimentally shown to improve both of these mechanical properties. In this work, we study the effect of 3D interfaces in the hexagonal close packed (HCP)/body centered cubic (BCC) Ti/Nb nanolaminate system. Nanoindentation hardness testing suggests increased strength with the introduction of a 3D Ti-Nb interface and a positive size effect with increases in 3D interface thickness from 5 nm to 20 nm. To understand this effect from a single dislocation perspective, we present a phase-field dislocation dynamics (PFDD) model for multi-phase HCP/BCC systems. We employ the model to simulate stress-driven transfer of single dislocations across 3D Ti/Nb interfaces of various thicknesses. Our results show that the critical stress for slip transfer increases with the thickness of the interface. This positive size effect is stronger for transfer from basal or prismatic dislocations in the Ti layer to 110<span><span><math><mrow is=\"true\"><mo is=\"true\">〈</mo><mn is=\"true\">111</mn><mo is=\"true\">〉</mo></mrow></math></span><script type=\"math/mml\"><math><mrow is=\"true\"><mo is=\"true\">〈</mo><mn is=\"true\">111</mn><mo is=\"true\">〉</mo></mrow></math></script></span> dislocations in the Nb layer than the reverse. For this Ti/Nb system, a critical thickness of 2 nm is identified at which the asymmetry in slip transfer is minimized. This work showcases 3D interfaces as a beneficial microstructure modification to strengthen as well as reduce anisotropy in nanocrystalline materials containing HCP phases.","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"56 1","pages":""},"PeriodicalIF":9.8,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142989913","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":"Mechanical responses and microstructure evolution of DP780 in complete σxx-σyy space: experiments and crystal plasticity characterization","authors":"Xuejian Yang, Mingyang Jiao, Zhijia Liu, Hui Zhao, Yan Peng, Lu Wu, Yu Wu, Rongjian Pan, Baodong Shi","doi":"10.1016/j.ijplas.2025.104247","DOIUrl":"https://doi.org/10.1016/j.ijplas.2025.104247","url":null,"abstract":"During practical forming processing, strong anisotropic mechanical behavior of dual phase (DP) steels is usually detected due to texture, which further determines subsequent processing optimization with loading paths changing. In order to clarify the underlying deformation mechanisms of DP steels under multi-axial loading, the mechanical response of DP780 under different biaxial loading paths was examined in detail. More precisely, anisotropic behavior of DP780 in complete “σ_xx-σ_yy” space was investigated through mechanical testing, microstructure characterization, and crystal plasticity computation based on dislocation density. In particular, biaxial compression test of thin plate is realized by using specifically designed fixture, and consequently yield loci in complete “σ_xx-σ_yy” space is detected experimentally. It is found that stronger anisotropy is observed under biaxial loading compared with that under uniaxial loading at macro scale, and biaxial Bauschinger effect is detected with biaxial preloading. At the micro scale, the texture evolution is affected directly by loading paths, and the compression load contributes more to the texture evolution. The distribution of the Taylor Factor under different biaxial loading paths reveals the impact of tension and compression on the main activated slip systems (MASS). Under biaxial tension and biaxial compression loading, the MASS of DP780 is the {112} slip system. Under combined biaxial tension and compression loading, the MASS is the {110} slip system. Using crystal plasticity, the evolution of dislocation density under different biaxial loading is captured. The relationship between the biaxial Bauschinger effect and MASS is clarified. It is found that the dislocation multiplication of the {112} slip system is more affected by changes in loading path than the {110} slip system. And during the subsequent loading process, the {110} slip system transform to {112} by preloading. Additionally, the relationship between the alteration of the MASS and the evolution of texture, as well as the resulting macroscopic anisotropic behavior has been elucidated.","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"12 1","pages":""},"PeriodicalIF":9.8,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142988058","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":"A strain-path dependent unified constitutive model of titanium alloy coupling coarse grain subdivision and recrystallization: application to multi-directional hot deformation","authors":"Shiqi Guo, Siliang Yan, Liang Huang, Kezhuo Liu, Changmin Li","doi":"10.1016/j.ijplas.2025.104248","DOIUrl":"https://doi.org/10.1016/j.ijplas.2025.104248","url":null,"abstract":"Primary hot working, represented by multi-directional hot forging and annealing, is a crucial step in microstructure control and plays a decisive role in the ultimate performance of ultra-high strength titanium alloy components. However, the interaction mechanisms of multiple physical processes comprising work hardening, dynamic recovery, dynamic recrystallization and grain fragmentation under complex thermo-mechanical routes are not yet well known, which greatly limits the process optimization and control of primary hot working process. In order to accurately predict the macro-micro behaviors of coarse-grained titanium alloys during multi-directional hot deformation and annealing processes, a strain-path dependent unified constitutive model was established comprehensively considering the intragranular coarse grain subdivision (ICGS) caused by ribbon and transgranular subdivided continuous dynamic recrystallization (CDRX), as well as the boundary-based coarse grain subdivision (BCGS) composed of discontinuous dynamic recrystallization (DDRX) coupled with boundary expand CDRX, and the interaction of various mechanisms under dislocation configuration. Through the combination of large deformation framework and viscoplastic theory, the influence of thermo-mechanical loading path and strain rate on grain refinement efficiency was elucidated. In the present model, the cumulative effects of loading direction changes on the degree of grain fragmentation were well identified by defining a new geometric parameter, viz. the loading axis rotation angle of the passes. The ICGS mechanism was introduced to the grain evolution model for the first time, by establishing a quatitative correlation between shear strain and the volume fraction of grain internal subdivision. In this way, the through-process precision prediction of the refinement degree of characteristic regions under multi-directional deformation paths was finally realized by combining BCGS and ICGS mechanisms, and the evolution of mechanical behaviors and internal variables in the alternating multi-directional hot deformation with heat preservation were simulated. The predictive results of the model were consistent with experiments of the titanium alloy with an average error of 4.93% and the refinement degrees of coarse-grained structures under different strain rates, temperatures and cumulative multi-directional large strains were well captured. Moreover, the applicable grain size range of the present constitutive model within a wide strain range was extended to 4 orders of magnitude (from micrometer to centimeter), and the effectiveness of the model in identifying complex multi-directional loading, multiple annealing and the heredity of internal variables during primary hot deformation were validated.","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"57 1","pages":""},"PeriodicalIF":9.8,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142988057","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":"Unique transitions in uniform elongation and deformation mechanisms of a refractory medium-entropy alloy at cryogenic temperatures","authors":"Xianbing Zhang, Shubin Wang, Jie Wang, Xinyu Xu, Song Lu, Binbin He","doi":"10.1016/j.ijplas.2025.104245","DOIUrl":"https://doi.org/10.1016/j.ijplas.2025.104245","url":null,"abstract":"Refractory high-entropy alloys (RHEAs) and medium-entropy alloys (RMEAs) are potential candidates for high-temperature applications; dislocations play crucial roles in the plastic deformation of these alloys at both room and elevated temperatures. However, there is a significant deficiency in the understanding of their temperature-dependent microstructure-mechanical property correlations at low temperatures, which is crucial for evaluating their performance and ensuring service safety under variable-temperature conditions. This study investigated the mechanical properties and deformation mechanisms of a non-equiatomic Ti_48.9Zr_32.0Nb_12.6Ta_6.5 RMEA at ambient and cryogenic temperatures. Tensile testing revealed intriguing temperature-dependent behaviors: as the temperature decreased, yield strength increased, while uniform elongation (<em>UE</em>) followed an abnormal U-shaped trend. The RMEA exhibited good <em>UE</em> at 293 K (10.9%), but <em>UE</em> dropped sharply to 185 K (2.2%). However, <em>UE</em> peaked at 77 K (17.2%) along with the highest ultimate tensile strength. These indicated a transition in the deformation mechanisms. Microstructural analysis showed that considerable strain hardening at 293 K was owing to abundant dislocation interactions as well as {112}&lt;111&gt; twins. At 185 K, strain hardening weakened due to suppressed dislocation activity, whereas kinking prevented the ductile-to-brittle transition despite limited <em>UE</em>. The strong strain hardening and enhanced <em>UE</em> at 77 K were attributed to the twinning-induced plasticity effect from {332}&lt;113&gt; deformation twins. In conclusion, this study highlights the anomalous temperature-dependent mechanical behavior of this RMEA and the corresponding evolution of deformation mechanisms. The findings provide key insights into the alloy design and optimizing the performance of RHEAs/RMEAs for applications in cryogenic and variable-temperature environments.","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"6 1","pages":""},"PeriodicalIF":9.8,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142968449","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":"Understanding the stress-induced grain boundary migration behavior in a deformed Mg alloy: the role of deformation twin and grain rotation","authors":"Zijian Zhang, Lin Yuan, Jiaping Ma, Mingyi Zheng, Debin Shan, Bin Guo","doi":"10.1016/j.ijplas.2025.104244","DOIUrl":"https://doi.org/10.1016/j.ijplas.2025.104244","url":null,"abstract":"Stress-induced grain boundary (GB) migration plays a crucial role in plastic deformation, influencing the microstructure and mechanical properties of polycrystalline materials. While twinning and grain rotation are important deformation modes, their impact on the GB migration of Mg alloys remains unclear. This work builds the internal relationship between deformation twins, grain rotation, and stress-induced GB migration in a deformed Mg alloy by experiments and simulations. During the uniaxial compression experiment, the GB migration mainly occurs during the <span><math><mrow is=\"true\"><mo is=\"true\">{</mo><mrow is=\"true\"><mn is=\"true\">10</mn><mover accent=\"true\" is=\"true\"><mn is=\"true\">1</mn><mo is=\"true\">¯</mo></mover><mn is=\"true\">2</mn></mrow><mo is=\"true\">}</mo></mrow></math></span>tension twin thickening. Atomic simulations reveal that twin thickening results from the slip of interface dislocations along the basal plane (0001) under shear stress. When interface dislocations of twins are hindered by the GB, local stress concentrations lead to GB migration. A new factor <em>I</em>, derived from experimental results, serves as a criterion to differentiate migrated from non-migrated regions during twin thickening at the mesoscale. Grain rotation accompanied by GB migration occurs under mesoscale observations. The scalar disclinations density increases at the GB junctions due to rotation and the disclinations move with the GB migration. Local rotation associated with the formation of low-angle GBs accelerates local migration and contributes to GB serration. Crystal plasticity finite element simulations show that the additional shear stress caused by grain rotation promotes GB migration. Our findings help to understand the GB migration mechanisms of Mg alloys related to the application of Mg alloys through GB engineering.","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"67 1","pages":""},"PeriodicalIF":9.8,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142937615","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":"Improvement of work-hardening capability and strength of FeNiCoCr-based high-entropy alloys by modulation of stacking fault energy and precipitation phase","authors":"Lei Zhang, Zhiyu Feng, Zixian Xiong, Xinlong Zhang, Bingzhao Wu, Chunyu Zhao","doi":"10.1016/j.ijplas.2025.104242","DOIUrl":"https://doi.org/10.1016/j.ijplas.2025.104242","url":null,"abstract":"Face-centered cubic (FCC) structured FeNiCoCr high-entropy alloys (HEAs) generally demonstrate good plasticity but exhibit relatively low strength. To tackle this challenge, we suggest the following approaches: (1) enhancing work-hardening ability through reducing the stacking fault energy of the alloy system. (2) adjusting the composition of alloying elements to control the formation of precipitation phase, thus fortifying the matrix. Based on the aforementioned perspectives, a series of alloys Fe₂NiCoCr(VN)_x (x=0, 0.3, 0.5, 1.0) was designed by adjusting the Fe element content in FeNiCoCr HEAs, and then adding V and N alloying elements to the alloy. Experimental results show that Fe₂NiCoCr(VN)_0.5 HEAs exhibit high-quality work-hardening ability and strength. The yield strength enhanced from 150 MPa to 250 MPa, while the ultimate tensile strength was enhanced from 540 MPa to 800 MPa. This represents an increase of 66% in yield strength and 48% in ultimate tensile strength, respectively. And plasticity remained stable at 25%, outperforming most as-cast FCC-structured HEAs. The changes in stacking fault energy and the dislocation slip behaviors around the precipitation phase were also calculated by the Molecular Dynamics simulation software Large-scale Atomic/Molecular Massively Parallel Simulator. This study not only reduces costs but also provides insights into the tunability of the mechanical properties of materials through alloying non-equiatomic HEAs.","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"37 1","pages":""},"PeriodicalIF":9.8,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142937070","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":"Simultaneously enhancing strength and plasticity via direct ageing in additive manufactured Al–Ni–Sc–Zr alloys","authors":"Guandong Luo, Han Chen, Lei Hu, Chen Yang, Shuwei Zong, Yanchi Chen, Qing Lian, Hongze Wang, Zhe Chen, Yi Wu, Haowei Wang","doi":"10.1016/j.ijplas.2025.104243","DOIUrl":"https://doi.org/10.1016/j.ijplas.2025.104243","url":null,"abstract":"Eutectic Al alloys processed by laser powder bed fusion (LPBF) frequently display metastable cellular structures. The cells are susceptible to decomposition into nanoparticles during ageing. Furthermore, supersaturated solutes can result in additional precipitation during the ageing process. The complicated microstructure evolution observed in LPBF eutectic Al alloys necessitates a comprehensive investigation into their ageing behaviour, to identify the optimal strength and plasticity. Consequently, this study presents a systematic examination of the impact of direct ageing on microstructure evolution in an LPBF Al‒Ni‒Sc‒Zr alloy, analysing associated changes in strength and plasticity. The optimal ageing parameters for strength and plasticity are determined. The results demonstrate that the reduction in strength resulting from cell decomposition can be offset by the strengthening provided by nanoparticles formed due to cell wall spheroidisation and additional supersaturated solute precipitation, achieving excellent yield strength. Furthermore, the transformation of cells into nanoparticles significantly enhances the plasticity by increasing non-uniform strain, which is not well explained by the conventional work hardening theory. A detailed investigation suggests that direct ageing can alleviate dislocation pile-up and strain localisation around cell walls, and reduce the tendency for crack propagation along melt pool boundaries, resulting in a significant increase in non-uniform strain and ultimately, excellent tensile plasticity. This study demonstrates that direct ageing is an effective strategy for simultaneously enhancing the strength and plasticity of LPBF Al–Ni based alloys. The proposed plasticity mechanism offers a new insight into the plastic deformation behaviour of LPBF eutectic Al alloys.","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"37 1","pages":""},"PeriodicalIF":9.8,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142937011","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}