Materials Science and Engineering: A最新文献

{"title":"TiC nanoparticles tune phase stability and deformation mechanisms in directed energy deposition processed Fe60Co15Ni15Cr10 medium-entropy alloy composites","authors":"Soung Yeoul Ahn ,&nbsp;Eun Seong Kim ,&nbsp;Sang Guk Jeong ,&nbsp;Stefanus Harjo ,&nbsp;Takuro Kawasaki ,&nbsp;Wu Gong ,&nbsp;Hyun-Joong Kim ,&nbsp;Soon-Jik Hong ,&nbsp;Sun Ig Hong ,&nbsp;Hyeonseok Kwon ,&nbsp;Jung Gi Kim ,&nbsp;Hyoung Seop Kim","doi":"10.1016/j.msea.2026.149839","DOIUrl":"10.1016/j.msea.2026.149839","url":null,"abstract":"<div><div>Additive manufacturing (AM) of particle-reinforced metal matrix composites (MMCs) offers opportunities not only for mechanical strengthening but also for tailoring matrix phase stability and deformation behavior. In this study, TiC (2 wt%) nanoparticles were incorporated into Fe₆₀Co₁₅Ni₁₅Cr₁₀ (at%) medium-entropy alloy (MEA) using directed energy deposition (DED) process. Despite the severe thermal conditions of the DED process, a substantial fraction of TiC remained, while partial decomposition released C and Ti elements into the matrix. This chemical modification stabilized the γ-austenite matrix phase and suppressed deformation-induced martensitic transformation (DIMT), which is typically active in the Fe₆₀Co₁₅Ni₁₅Cr₁₀ MEA. Instead, the composite exhibited a transition toward slip-dominated deformation. Microstructural observation revealed that dispersed and semi-coherent TiC particles, together with solute partitioning from decomposed nanoparticles, altered grain boundary morphology and promoted distributed plastic flow. <em>In-situ</em> neutron diffraction accompanied with tensile test confirmed enhanced dislocation activity in the early stage of deformation, supporting the deformation mechanism shift from DIMT-assisted hardening to dislocation-mediated slip. These results highlight the critical role of nanoparticle-induced phase stability variation in governing deformation mechanisms, offering new insights into designing AM-processed MMCs beyond conventional strength-oriented strategies.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"955 ","pages":"Article 149839"},"PeriodicalIF":7.0,"publicationDate":"2026-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146077036","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":"Influence of single- and double-step solution and aging treatments on the microstructure, texture, and mechanical properties of cold-rolled Al–Cu–Li alloy sheets (Cu/Li ratios 2 and 4) produced via squeeze casting","authors":"S. Manojkumar,&nbsp;Yogesh Singh,&nbsp;K.K. Mehta","doi":"10.1016/j.msea.2026.149828","DOIUrl":"10.1016/j.msea.2026.149828","url":null,"abstract":"<div><div>Squeeze-cast Al–Cu–Li alloys, SC1 (Cu/Li ≈ 2, Li ≈ 1.28 wt%) and SC2 (Cu/Li ≈ 4, Li ≈ 0.53 wt%), studied in three heat-treatment conditions: H1 (single-step solution → quenching → double-aging), H2 (double-step solution → quenching → double aging), and H3 (double-step solution → quenching → single aging). Cold rolling of SC1 developed pronounced crystallographic textures, strongly influenced by the Cu/Li ratio and Li-content. Nearly double the Li in SC1 led to a fourfold increase in texture intensity compared to SC2, mainly from strong Copper <span><math><mrow><mo>(</mo><mrow><mrow><mo>{</mo><mn>112</mn><mo>}</mo></mrow><mspace></mspace><mrow><mo>⟨</mo><mn>111</mn><mo>⟩</mo></mrow></mrow><mo>)</mo></mrow></math></span> component. Heat treatment markedly influenced the strength–ductility trade-off. In SC1, the H1 condition achieved nearly twice the strength of H3 but incurred a twofold reduction in ductility, attributed to a higher fraction of T1 (Al₂CuLi) precipitates formed during double aging. SC2 displayed superior ductility but limited strength, particularly under H3 treatment. Mechanical performance was governed by the combined effects of solution treatment, controlling grain size and texture, and aging treatment, regulating precipitation. The superior strength of SC1 in H1 condition arose from the synergistic effect of refined grains with strong Cube texture and enhanced T1 precipitation. Conversely, low Li content in SC2 restricted T1 precipitation, limiting strengthening. H3 triggers dislocation looping and serrations in stress–strain curves via T2 (Al₆CuLi₃) precipitates, while H1 (SC1) suppresses serrations by depleting Cu and Li through high T1 precipitation. Constitutive modeling using the Voce's-relationship and KM-model showed excellent agreement with experiments, providing a robust framework for optimizing heat-treatment routes for Al–Cu–Li alloys.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"955 ","pages":"Article 149828"},"PeriodicalIF":7.0,"publicationDate":"2026-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146077035","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":"Effects of Al-5Ti-1B-xCe refiners on microstructure and tensile properties of Al-5.0Mg-3.0Zn-1.0Cu alloy at different cooling rates","authors":"Shenshen Cui ,&nbsp;Qiang Lu ,&nbsp;Dezhi Li ,&nbsp;Haiyan Jiang ,&nbsp;Qudong Wang ,&nbsp;Huisheng Cai","doi":"10.1016/j.msea.2026.149820","DOIUrl":"10.1016/j.msea.2026.149820","url":null,"abstract":"<div><div>In this investigation, the effects of Al-5Ti-1B-xCe (x = 0, 4, 8, 12 wt%) refiners on the grain size, microstructure, and mechanical properties of the Al-5.0Mg-3.0Zn-1.0Cu alloy under different cooling rates were investigated. The results showed that, within the cooling rate range of 9.5–33.6 °C/s, the Al-5Ti-1B-xCe (x = 4, 8, 12) refiners exhibit superior refinement effects on the secondary dendrite arm spacing (SDAS), the width of the Mg₃₂(AlCuZn)₄₉ phase, and the size of the Al₃Fe phase in the Al-5.0Mg-3.0Zn-1.0Cu alloy compared with the Al-5Ti-1B refiner, and the Al-5Ti-1B-4Ce refiner exhibits the strongest grain-refining effect. Moreover, as the cooling rate increases, the grain size, SDAS, the width of the Mg₃₂(AlCuZn)₄₉ phase, and the size of the Al₃Fe phase are refined, while in the aged condition, the precipitation-free zone (PFZ) width and the size of precipitates is reduced. Compared with the alloy refined by the Al-5Ti-1B refiner, the alloys refined by Al-5Ti-1B-xCe (x = 4, 8, 12) exhibit a reduced sensitivity of grain size to cooling rate; therefore, as the cooling rate increases, the extent of grain size reduction in the alloys refined by Al-5Ti-1B-xCe (x = 4, 8, 12) becomes smaller. The precipitate diameter shows a unimodal distribution when the alloy is refined by the Al-5Ti-1B refiner, while a bimodal distribution is observed after refinement by the Al-5Ti-1B-xCe (x = 4, 12) refiners. Compared with the alloy refined by the Al-5Ti-1B refiner, the aged Al-5.0Mg-3.0Zn-1.0Cu alloy refined by the Al-5Ti-1B-4Ce and Al-5Ti-1B-8Ce refiners exhibit higher strength and elongation. For alloys refined by the same refiner, the strength and elongation of the aged Al-5.0Mg-3.0Zn-1.0Cu alloy increase with increasing cooling rate.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"954 ","pages":"Article 149820"},"PeriodicalIF":7.0,"publicationDate":"2026-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146037420","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":"Strengthening and toughening of developed high-strength hull structural steel and its heat-affected zones","authors":"Deng-Bang Gao ,&nbsp;Xuan-Wei Lei ,&nbsp;Hai-Tao Jian ,&nbsp;Chun-Long Jiang ,&nbsp;Zhi Cheng ,&nbsp;Ji-Hua Huang","doi":"10.1016/j.msea.2026.149793","DOIUrl":"10.1016/j.msea.2026.149793","url":null,"abstract":"<div><div>A high-strength hull structural (HSHS) steel was developed based on a low-carbon high-nickel design concept. To evaluate its mechanical properties and weldability, the microstructures and mechanical performance of both the base metal and its heat-affected zones (HAZs)—including the coarse-grained HAZ, fine-grained HAZ, unaltered coarse-grained HAZ, and supercritically reheated coarse-grained HAZ—were systematically investigated under heat inputs of 20 and 50 kJ/cm. The strengthening and toughening mechanisms of the HSHS steel and its HAZs were further elucidated. The results demonstrate that the developed HSHS steel exhibits excellent comprehensive mechanical properties, while its HAZs maintain sufficiently high strength and overall satisfactory toughness at 223 K (−50 °C). The high strength of the developed HSHS steel is primarily attributed to the second phase precipitation and the formation of a tempered bainite-dominated microstructure. In the HAZs, the designed Nb content and the development of a lath-based microstructure are identified as key factors ensuring high strength. The low-temperature toughness of both the base metal and HAZs is predominantly governed by the high Ni content and refined M-A constituents, with secondary contributions from finer effective grain size and microstructural characteristics. Depending on specific conditions, these factors lead to variations in Charpy impact energy. Notably, a comparative analysis with documented data reveals that the mechanical properties of the HAZs in the developed HSHS steel are comparable to those of HSLA-100 steels. Collectively, these findings confirm that the developed HSHS steel possesses good weldability.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"954 ","pages":"Article 149793"},"PeriodicalIF":7.0,"publicationDate":"2026-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146037422","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":"Synergistic strength and ductility enhancement of lightweight AlTiVCr eutectic high entropy alloys with controlled Al/Ti atomic ratios","authors":"Dong Seong Hong ,&nbsp;Sung Hwan Hong ,&nbsp;Yu Jin Lee ,&nbsp;Ga Eun Jo ,&nbsp;Dilshodbek Yusupov ,&nbsp;Muhammad Aoun Abbas ,&nbsp;Gyeol Chan Kang ,&nbsp;Hae Jin Park ,&nbsp;Jürgen Eckert ,&nbsp;Kiran P. Shinde ,&nbsp;Ki Buem Kim","doi":"10.1016/j.msea.2026.149817","DOIUrl":"10.1016/j.msea.2026.149817","url":null,"abstract":"<div><div>Eutectic high entropy alloys (EHEAs) based on the AlTiVCr system offer a promising combination of high strength and ductility, making them attractive for advanced structural applications. In the present work, a simple and effective strategy of varying two constituent elements Al and Ti was proposed to design EHEA. Al_xTi_80-xV₁₅Cr₅ (x = 35, 40, 45 at.%) alloy compositions were prepared by arc suction casting. The Al₃₅Ti₄₅V₁₅Cr₅ alloy exhibited a single B2 phase structure. With increasing Al content, the microstructure of Al₄₀Ti₄₀V₁₅Cr₅ evolved to a dual-phase structure composed of a high amount of B2 matrix with locally distributed HCP phase, and the Al₄₅Ti₃₅V₁₅Cr₅ alloy formed as a eutectic structure consisting of B2 and HCP phases. The Al₄₅Ti₃₅V₁₅Cr₅ EHEA composition demonstrates a high yield strength of 1864 MPa and excellent compressive ductility of 14.3 %, attributed to the suppression of shear band propagation at the phase boundaries, and it exhibited a low density of 3.97 g/cm³, leading to a superior specific strength of 469.22 MPa cm³/g. The stable intermetallic-based eutectic microstructures were achieved by tuning the composition in accordance with the strong negative mixing enthalpy between Al and Ti. The formation of a eutectic dual-phase microstructure consisting of B2 and HCP phases significantly enhances the mechanical performance. These findings give a new pathway for designing lightweight, high-performance eutectic high entropy alloys.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"954 ","pages":"Article 149817"},"PeriodicalIF":7.0,"publicationDate":"2026-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146037424","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":"Engineered ωiso phase enable deformation-induced mechanisms strength and plasticity synergy in a novel Ti-531 metastable β titanium alloy","authors":"Irfan Ali Abro ,&nbsp;Lin Yang ,&nbsp;Qunbo Fan ,&nbsp;Kamal Mustafa","doi":"10.1016/j.msea.2026.149806","DOIUrl":"10.1016/j.msea.2026.149806","url":null,"abstract":"<div><div>Metastable β-Ti alloys are known for their high strain hardening rates and excellent plasticity through the combined effects of transformation induced plasticity (TRIP) and twinning induced plasticity (TWIP) effects, yet their relatively low yield strength restrict structural applications. Improving yield strength without sacrificing ductility is thus a key challenge in these alloys. To address this long-standing strength-plasticity dilemma, we designed a novel metastable β-Ti alloy, Ti-5Mo-3Cr-1Zr (Ti-531), guided by d-electron theory, average electron-to-atom ratio <span><math><mrow><mo>(</mo><mover><mrow><mi>e</mi><mo>/</mo><mi>a</mi></mrow><mo>‾</mo></mover><mo>)</mo></mrow></math></span> and atomic radius difference <span><math><mrow><mo>(</mo><mover><mrow><mo>Δ</mo><mi>r</mi></mrow><mo>‾</mo></mover><mo>)</mo></mrow></math></span> criteria. By engineering nanoscale <span><math><mrow><msub><mi>ω</mi><mtext>iso</mtext></msub></mrow></math></span> phase precipitations, a strategy is demonstrated to concurrently strengthen the yield response and preserve high ductility in the Ti-531 alloy. The results show that these <span><math><mrow><msub><mi>ω</mi><mtext>iso</mtext></msub></mrow></math></span> particles substantially strengthen the alloy and activate a synergistic deformation-induced strengthening mechanism. This mechanism involves a sandwich-type composite twin/stress-induced <span><math><mrow><mi>ω</mi></mrow></math></span> <span><math><mrow><mo>(</mo><msub><mtext>SI</mtext><mi>ω</mi></msub><mo>)</mo></mrow></math></span> structures, interactions between twin/SIM (α”), and development of dislocation channels largely devoid of <span><math><mrow><msub><mi>ω</mi><mtext>iso</mtext></msub></mrow></math></span> phase synergistically accommodate localized strain. These dislocation channels facilitate to accelerate dislocation accumulation, promote forest hardening and suppress the impeding effect of <span><math><mrow><msub><mi>ω</mi><mtext>iso</mtext></msub></mrow></math></span> phase. As a result, the alloy aged at 423 K (A423) outperforms the hot-rolled solution-treated alloy (R1123) in yield strength (∼642 MPa, ∼28 % higher) with merely a slight (∼1.1 %) reduction in elongation, thus combining high strength with largely preserved ductility. This work introduces instability-control paradigm that harmonizes twin/ <span><math><mrow><msub><mtext>SI</mtext><mi>ω</mi></msub></mrow></math></span>/SIM-assisted deformation and dislocation channels strengthening to engineer high performance metastable β-Ti alloys.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"954 ","pages":"Article 149806"},"PeriodicalIF":7.0,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146006806","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":"Design strategy for enhancing mechanical properties and magnetocaloric effect of eutectic Ni-Mn-Sn-Fe alloy via laser powder bed fusion","authors":"Rongzhi Li ,&nbsp;Peter K. Liaw ,&nbsp;Jianzhong Jiang ,&nbsp;Lin Deng ,&nbsp;Yong Zhang","doi":"10.1016/j.msea.2026.149795","DOIUrl":"10.1016/j.msea.2026.149795","url":null,"abstract":"<div><div>Environmental concerns from conventional refrigerants highlight the urgent need for solid-state cooling materials that combine structural robustness with strong magnetocaloric performance. Here, we design a dual-phase Ni₅₀Mn₃₂Sn₁₀Fe₈ Heusler alloy using Fe alloying in conjunction with optimized laser powder bed fusion (L-PBF) and homogenization annealing. The resulting ultrafine eutectic structure (∼650 nm lamellar spacing) with semi-coherent Kurdjumov–Sachs interfaces effectively integrates mechanical strength and functional performance. The alloy exhibits high compressive strength (1692.8 MPa), good ductility (10.5 %), and a stable modulus (∼113 GPa) with ∼1.4 % recoverable superelastic strain after 50 cycles. Functionally, it achieves a magnetic entropy change of 10.04 J kg⁻¹ K⁻¹ and a refrigerant capacity of 184 J/kg under a 5 T magnetic field. This work establishes a composition–processing design strategy for multifunctional magnetocaloric materials, providing a pathway toward robust, high-performance alloys for solid-state cooling, flexible actuators, and biomedical devices.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"954 ","pages":"Article 149795"},"PeriodicalIF":7.0,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146006807","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":"Heterogeneous deformation and strengthening mechanism in TC4 coaxial laser wire-based directed energy deposition for repairing Ti80","authors":"Xiaohong Zhan ,&nbsp;Jinsheng Ji ,&nbsp;Chaoqi Qi ,&nbsp;Xiong Zhang ,&nbsp;Deliang Lei ,&nbsp;Jianfeng Wang","doi":"10.1016/j.msea.2026.149800","DOIUrl":"10.1016/j.msea.2026.149800","url":null,"abstract":"<div><div>Laser additive manufacturing technology holds great potential for repairing titanium alloys. In this study, coaxial laser wire-based directed energy deposition (CLW-DED) using TC4 alloy was first applied to repair forged Ti80 alloy, with a focus on investigating the regional microstructural variations and synergistic deformation behavior of the repaired specimens. Additionally, the strengthening effects of dual annealing treatments were explored. The results revealed that the microstructure of the repaired specimens transitioned from fine α′ martensite in the repaired zone to the equiaxed α phase in the substrate. Heat treatment induced martensite decomposition and facilitated element diffusion, contributing to the stabilization of the microstructure. The repaired sample demonstrated superior strength to the substrate material with substantially reduced plasticity. The mismatch in strength and ductility was primarily attributed to strain concentration and differences in strain hardening rates at the interface between the repaired layer and the substrate. Dislocation slip served as the primary deformation mechanism, while twinning was activated as a secondary deformation mechanism in the repaired layer. Heat treatment enhanced the tensile strength of the specimens to ∼982 MPa and improved ductility to ∼5.2 % by reducing dislocation density and promoting dislocation slip. This study confirms the feasibility of CLW-DED for titanium alloy repair and provides theoretical insights into the mechanical performance of the heterostructured metallic components.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"953 ","pages":"Article 149800"},"PeriodicalIF":7.0,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146023555","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, texture evolution and mechanical properties of Mg-4Y-2Nd-2Sm-0.5Zr alloy under different hot extrusion ratios","authors":"Zheng Wu ,&nbsp;Xiaoya Chen ,&nbsp;Jian Zeng ,&nbsp;Kang Yao ,&nbsp;Dongzhen Wang ,&nbsp;Quanan Li","doi":"10.1016/j.msea.2026.149810","DOIUrl":"10.1016/j.msea.2026.149810","url":null,"abstract":"<div><div>Achieving a significant enhancement in the mechanical properties of Mg-Y-RE (WE) alloys is critical for broadening their application prospects. This study systematically examines and discusses the dynamic recrystallization (DRX) and dislocation behavior of WE alloys under different extrusion ratios. Examination of the microstructure of the extruded alloys reveals that varying hot extrusion ratios influence recrystallization behavior, with grain refinement being highly correlated with particle stimulated nucleation (PSN) and continuous/discontinuous dynamic recrystallization (CDRX/DDRX) mechanisms. Furthermore, an increase in the extrusion ratio enhances dynamic precipitation, thereby promoting the formation of fine and uniform precipitates. At an extrusion ratio of 9.4, the yield strength (YS) reaches 312 MPa and the elongation (EL) improves to 11.1 %. The observed enhancements can be primarily linked to the processes of grain refinement and the activation of pyramidal slip. This approach allows for a deeper comprehension of the intricate interplay between microstructural characteristics and the mechanical properties inherent to Mg alloys. Moreover, it serves as a significant reference point for the industrial manufacturing of high-performance extruded Mg-Y series alloys, optimizing their overall performance in practical applications.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"953 ","pages":"Article 149810"},"PeriodicalIF":7.0,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146023553","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":"Temperature-dependent deformation mechanisms and strengthening behavior of a novel Ni-based superalloy with bimodal γ′ precipitate distribution","authors":"Xinyu Meng ,&nbsp;Chao Tang ,&nbsp;Shaomin Lyu ,&nbsp;Xingfei Xie ,&nbsp;Jian Jia ,&nbsp;Jinglong Qu","doi":"10.1016/j.msea.2026.149784","DOIUrl":"10.1016/j.msea.2026.149784","url":null,"abstract":"<div><div>High-temperature tensile performance is a critical indicator of the mechanical reliability of Ni-based superalloys. In this study, a newly designed Ni-based superalloy was systematically investigated from room temperature to 900 °C to elucidate the coupling between microstructural characteristics, mechanical response, and deformation mechanisms. Fine-grained (10.7 μm) and coarse-grained (97 μm) microstructures were obtained through multi-stage heat treatments. The FG alloy exhibits superior yield and tensile strength below 750 °C, reaching 1340 MPa and 1740 MPa at room temperature and retaining 1208 MPa and 1267 MPa at 750 °C, which is primarily attributed to its higher grain boundary density and enhanced grain-boundary-mediated strengthening. However, the FG alloy shows a pronounced ductility drop at 815 °C, with the elongation decreasing to 9 %. In contrast, the CG alloy demonstrates enhanced strength retention at elevated temperatures, maintaining an ultimate tensile strength and yield strength of 801 MPa and 770 MPa at 900 °C, corresponding to a tensile strength retention of 54 % (compared with 38 % for the FG alloy), together with a stable elongation of 8.5 %. This superior high-temperature stability is associated with a lower grain boundary density and a higher fraction of Σ3 special boundaries (42.6–55.9 %). Microstructural analysis reveals a bimodal γ′ precipitate distribution in both microstructures, with fine secondary γ′ precipitates (FG: 82 nm, 48 %; CG: 92 nm, 57 %) dominating strengthening through short-range dislocation–precipitate interactions, and coarse primary γ′ precipitates (FG: 1.54 μm, 7.6 %; CG: 3.19 μm, 0.5 %) facilitating deformation accommodation by pinning grain boundary migration, thereby enabling a synergistic balance between strength and ductility over a wide temperature range. Transmission electron microscopy and critical resolved shear stress analysis demonstrate a temperature-dependent transition in deformation mechanisms from γ′ shearing to Orowan looping in the range of 815–900 °C. In addition, Co/Ti solute segregation at twin interfaces reduces interfacial energy and suppresses defect migration, further stabilizing the γ/γ′ microstructure and enhancing high-temperature strength. These findings provide mechanistic insight for the microstructural design of advanced Ni-based superalloys.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"953 ","pages":"Article 149784"},"PeriodicalIF":7.0,"publicationDate":"2026-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146023554","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}