Materials Science and Engineering: A最新文献

{"title":"Ultrastrong nanocrystalline FeCoNiCr high entropy alloy with outstanding thermal stability","authors":"Guoying Liu,&nbsp;Youyue Jiang,&nbsp;Chenjing Ma,&nbsp;Zhen Yuan,&nbsp;Baoru Sun,&nbsp;Tongde Shen","doi":"10.1016/j.msea.2025.148282","DOIUrl":"10.1016/j.msea.2025.148282","url":null,"abstract":"<div><div>FeCoNiCr-based high-entropy alloys (HEAs) exhibit excellent irradiation resistance and outstanding mechanical performance, particularly at cryogenic temperatures, rendering them strong candidates for manufacturing high-performance parts in extreme environments. Nanocrystalline (NC) FeCoNiCr-based HEAs exhibit greater strength compared to their coarse-grained (CG) equivalents. Yet, their thermal stability is often subpar. The reason is that the nanograins experience considerable coarsening upon heating to a temperature between 0.4 and 0.6 of their melting point (<em>T</em>_m). In this work, we report an NC FeCoNiCr HEA, containing 1 at% lanthanum (NC FeCoNiCr-La HEA), synthesized via mechanical alloying (MA) and high temperature &amp; high pressure (HTHP) sintering methods, with an average grain diameter of 59 nm and an exceptionally high hardness of 715 HV, displaying prominent thermal stability up to 1000 °C (0.74<em>T</em>_m). The thermal stability is explained by the segregation of elemental lanthanum and La-O-rich nanoprecipitates (NPs) at the grain boundaries (GBs).</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"933 ","pages":"Article 148282"},"PeriodicalIF":6.1,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777590","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":"Improving the plasticity of transition-metal-based high-entropy bulk metallic glasses via Ag-induced phase separation","authors":"Xueru Fan ,&nbsp;Lei Xie ,&nbsp;Qiang Li ,&nbsp;Chuntao Chang","doi":"10.1016/j.msea.2025.148281","DOIUrl":"10.1016/j.msea.2025.148281","url":null,"abstract":"<div><div>High-entropy bulk metallic glasses (HE-BMGs) exhibit unique combinations of mechanical and magnetic properties due to their complex compositions. This study investigates the effects of minor Ag additions on the glass-forming ability (GFA), thermal stability, and mechanical behavior of [Fe_0.25Co_0.25Ni_0.25(Si_0.3B_0.7)_0.25]_100-xAg_x (x = 0, 0.1, 0.3, 0.5 at.%) HE-BMGs. Results indicate that Ag promotes phase separation, introducing nanoscale heterogeneity, which enhances plasticity and mechanical performance. Optimal Ag content (0.3 at.%) achieved an 15.7 % plastic strain and 3875 MPa yield strength, attributed to the formation of short-range ordered structures and shear transformation zones. These nanoscale heterogeneities acted as pinning sites, facilitating shear-band branching and stable deformation. Excessive Ag content, however, induced brittle phase formation and structural stress, reducing plasticity. Furthermore, the saturation magnetization peaked at 0.84 T with minimal degradation of GFA. These findings highlight the potential of controlled phase separation in designing HE-BMGs with superior strength-ductility synergy for advanced structural applications.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"932 ","pages":"Article 148281"},"PeriodicalIF":6.1,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768575","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":"Laser directed energy deposition of thin-walled GH4099 superalloy with gradient microstructure and mechanical properties","authors":"Xinyu Zhang ,&nbsp;Shiyu Wang ,&nbsp;Yongfeng Liang ,&nbsp;Yingchao Guo ,&nbsp;Zhichao Guo ,&nbsp;Feng Yi ,&nbsp;Junpin Lin","doi":"10.1016/j.msea.2025.148283","DOIUrl":"10.1016/j.msea.2025.148283","url":null,"abstract":"<div><div>The present study used laser-directed energy deposition(L-DED) to manufacture a GH4099 superalloy thin-walled structure with a gradient microstructure and mechanical properties. A systematic analysis examined the heat-driven changes in microstructure and both microscopic and macroscopic mechanical properties along the build direction. Columnar crystal epitaxial growth increased from bottom to top, while heat flow transformed intergranular impurities into tiny columnar crystals. Non-equilibrium solidification dendrites introduced fluctuations in elastic modulus and hardness. The substantial increase in microscopic mechanical properties observed with height primarily stemmed from variations in γ' characteristics with respect to height. The increase in grain size and precipitate size leads to a gradual decrease in the gradient of macroscopic mechanical properties from bottom to top. Intragranular carbides are primarily attributed to the γ/γ' interface and regions near dislocations, whereas intergranular carbides grow along specific orientations and are pinned at grain boundaries.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"933 ","pages":"Article 148283"},"PeriodicalIF":6.1,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768501","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":"Improving the mechanical properties and superelasticity of NiTiFe shape memory alloys through heterogeneous structures","authors":"Peiqian Zhang ,&nbsp;Ningxin Li ,&nbsp;Tengfeng Feng ,&nbsp;Zhengyang Luo ,&nbsp;Lei Xiao ,&nbsp;Xinkai Ma","doi":"10.1016/j.msea.2025.148284","DOIUrl":"10.1016/j.msea.2025.148284","url":null,"abstract":"<div><div>This study prepared three different microstructures of NiTiFe shape memory alloys (SMAs) through cold rolling and recrystallization annealing. Among them, the heterostructure (HS) type alloy achieved a synergistic combination of strength and ductility while improving its superelastic stability. The ultimate tensile strength of the HS type alloy was 912 MPa, with a uniform elongation of 21.78 %. The residual strain after a single tensile cycle at 7 % strain was 2.66 %, and after ten tensile cycles, the residual strain was 2.69 %. The initial morphology and post-stretching deformation of the NiTiFe SMAs were captured using electron backscatter diffraction (EBSD), revealing the distribution of grain size, high-angle grain boundaries, subgrain boundaries, kernel average misorientation (KAM), and geometrically necessary dislocation (GND) density for all three microstructures. Based on the &lt;111 &gt;/, &lt;100 &gt;/{110}, and &lt;100 &gt;/{010} slip systems, the maximum Schmid factor for each grain slip system in NiTiFe SMAs was obtained. The HS type NiTiFe exhibited superior overall performance due to the synergistic effect of its unique recrystallized grains and non-recrystallized regions. This study provides valuable insights into improving the comprehensive performance of NiTiFe SMAs, which can be applied in a wide range of engineering applications.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"932 ","pages":"Article 148284"},"PeriodicalIF":6.1,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143746466","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":"Investigation of secondary phases evolution and mechanical properties of ultra-high strength aluminum alloy driven by Cu element","authors":"Lei Jiang ,&nbsp;Zhilin Han ,&nbsp;Xinbiao Zhang ,&nbsp;Wentao Zhoutai ,&nbsp;Ziyao Zhao ,&nbsp;Zhihao Zhang ,&nbsp;Jianxin Xie","doi":"10.1016/j.msea.2025.148285","DOIUrl":"10.1016/j.msea.2025.148285","url":null,"abstract":"<div><div>The synergistic effect of multi-scale secondary phases is the primary source of the excellent mechanical properties for ultra-high strength aluminum alloys. Investigating the role of Cu, a key element in secondary phase formation, is fundamental to achieving precise microstructure-property control. In this study, Al-10.50Zn-2.35Mg-<em>x</em>Cu-0.12Cr-0.1Mn-0.1Zr-0.06Ti alloys (<em>x</em> = 0.0, 1.3, 2.2 wt.%) were selected to examine the influence of Cu content on the morphology of secondary phases, elemental distribution, and mechanical properties in both single-stage aging (T6) and retrogression and re-aging (RRA) conditions. The results indicate that, compared to the 0Cu sample, the 1.3 wt.% Cu alloy exhibits a significant increase in the volume fraction of precipitates in the T6 condition, with a transformation of the dominant precipitates from GPI zones to GPII and η′ phases. Consequently, the ultimate tensile strength (UTS) increases from 739 ± 2 MPa to 779 ± 3 MPa, with minimal change in elongation. However, in the 2.2 wt.% Cu alloy, the T6 treatment leads to the formation of micron- and submicron-sized σ phases (Al, Zn, Mg, Cu), consuming solute elements necessary for nanoscale precipitate formation. This reduces the nucleation sites for early-stage precipitates and promotes precipitate coarsening, ultimately leading to a decrease in both strength and ductility. In the RRA condition, the primary precipitate in the 0Cu alloy is the T′ phase. The addition of Cu facilitates the transformation of T′ to η′ phase while inhibiting the η′ to η phase transition and suppressing precipitate coarsening. With increasing Cu content, the average precipitate size in all three RRA alloys decreases, and the UTS gradually improves. Furthermore, Cu content exhibits a positive correlation with UTS_RRA/UTS_T6, suggesting that increasing Cu content can enhance the strength of the RRA-treated samples beyond that of the T6-treated ones.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"933 ","pages":"Article 148285"},"PeriodicalIF":6.1,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777591","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":"Anomalous precipitation behavior in T-phase strengthened Al-Mg-Zn(-Cu) alloys: Effects of aging temperatures and Cu contents","authors":"Songbai Tang ,&nbsp;Xiaodong Wu ,&nbsp;Lingfei Cao ,&nbsp;Yan Zou ,&nbsp;Min Bai ,&nbsp;Yurong Yang","doi":"10.1016/j.msea.2025.148287","DOIUrl":"10.1016/j.msea.2025.148287","url":null,"abstract":"<div><div>The anomalous precipitation behavior, characterized by a decline in hardening rates with increasing aging temperature, was systematically investigated in Al-Mg-Zn(-Cu) crossover alloys. Hardness testing, tensile testing and transmission electron microscopy (TEM) observation were employed to elucidate the relationships among aging temperature, Cu content and the hardening behavior, as well as relevant microstructural evolution. The results indicate that this unique behavior is associated with the evolution of T phase, which is strongly influenced by aging temperatures and Cu contents. High aging temperatures are detrimental to T-phase nucleation, resulting in the formation of low-density precursors with distinctive substructure unit of T″ phase at the early stage of aging. So that insufficient nuclei are provided for the subsequent development of hardening phase. During the prolonged aging at elevated temperatures, T phase undergoes rapid coarsening, leading to a significant reduction in the hardening potential of the alloys. Such detrimental effects of high-temperature aging can be mitigated by Cu addition, which enhances the density of precursors for T-phase and improves the thermal resistance of precipitates during the later aging stages. These beneficial effects become more pronounced with increasing Cu content. Based on these findings, strategies for designing high-strength Al-Mg-Zn(-Cu) alloys were outlined, emphasizing the control of early precursors of T phase through optimized aging treatments.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"933 ","pages":"Article 148287"},"PeriodicalIF":6.1,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768500","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":"Achieving excellent cryogenic strength-ductility synergy of ultra-low carbon austenite stainless steel by cryogenic rolling and two-step annealing","authors":"Wenping Sun ,&nbsp;Bin Fu ,&nbsp;Yanhui Guo ,&nbsp;Yu Li ,&nbsp;Linghuan Pang","doi":"10.1016/j.msea.2025.148270","DOIUrl":"10.1016/j.msea.2025.148270","url":null,"abstract":"<div><div>This study proposes a novel processing method combining cryogenic rolling (cryo-rolling) and a two-step annealing process to further enhance the heterogeneity of 316L austenitic stainless steel. Deformation-induced martensite (DIM) was formed after cryo-rolling due to the reduction in stacking fault energy (SFE), accompanied by microstructural refinement and dislocation accumulation. After the first annealing at 700 °C, most of the DIM reverted to austenite with fine grains (FG, 1∼5 μm), while the stored energy was significantly reduced. In the second annealing at 750 °C, recrystallization became the dominant mechanism of microstructural evolution, resulting in a microstructure consisting of ultrafine grains (UFG, &lt;1 μm), fine grains (FG), and coarse grains (CG, &gt;5μm). After the two-step annealing process, an excellent combination of mechanical properties was achieved, including a yield strength (YS) of 1057 MPa, an ultimate tensile strength (UTS) of 1510 MPa, and a total elongation (EL) of 62.5%. The high YS primarily arises from UFG and dislocation strengthening. The enhancement of heterogeneity facilitated the interaction between UFG, FG, and CG, significantly improving the strain-hardening ability, which can primarily be attributed to the heterogeneous deformation-induced (HDI) effect in the early deformation stage. The transformation-induced plasticity (TRIP) effect was identified as the main mechanism in the later deformation stage.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"932 ","pages":"Article 148270"},"PeriodicalIF":6.1,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768577","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 related mechanical properties of additively manufactured Ti2AlC-modified Inconel 718 superalloy during long-term thermal exposure","authors":"Huihui Wang ,&nbsp;Qianying Guo ,&nbsp;Chong Li ,&nbsp;Lei Cui ,&nbsp;Haining Yao ,&nbsp;Yongchang Liu","doi":"10.1016/j.msea.2025.148272","DOIUrl":"10.1016/j.msea.2025.148272","url":null,"abstract":"<div><div>Ti₂AlC has been shown to significantly enhance the mechanical properties of Inconel 718 (IN718). For its reliable application in high-temperature environments, understanding its microstructural evolution and mechanical behavior under prolonged thermal exposure is crucial but remains underexplored. This study investigates the microstructural evolution and mechanical properties of laser powder bed fusion (LPBF) fabricated Ti₂AlC-modified IN718 during long-term thermal exposure at 760 °C. The results reveal that (Ti, Nb)C carbides formed from Ti₂AlC decomposition coarsened according to the Lifshitz-Slyozov-Wagner (LSW) model, while σ phases nucleated and grew along grain boundaries adjacent to carbides. The thermal stability of γ″ and γ′ in co-precipitates inhibited the transformation of metastable γ″ to δ phases, contributing to microstructural stability. Cellular structures were stabilized by the pinning effects of (Ti, Nb)C carbides, with boundaries covered by elongated γ″ phases during thermal exposure. This led to Nb depletion within sub-grains, limiting γ″ growth in co-precipitates and driving a stacking sequence evolution from γ″/γ′/γ″ to γ′/γ″/γ′. The coarsening of elongated γ″ precipitates triggered a transition in deformation mechanisms from dislocation shearing to micro-twinning. In regions where cellular structures were annihilated, γ′ and γ″ coarsened slowly, with some γ″/γ′/γ″ evolving into γ′/γ″ duplets, maintaining shearing as the dominant deformation mechanism. Tensile tests at 650 °C demonstrated a continuous decrease in yield strength (YS), primarily attributed to the coarsening of σ phases and the reduction in γ″/γ′/γ″ triplets. Conversely, ductility improved significantly from 9.6 % to 21.1 %, driven by the activation of micro-twinning and enhanced dislocation motion facilitated by coarsened precipitates. These findings highlight the importance of Ti₂AlC in stabilizing the microstructure and optimizing the high-temperature performance of IN718 alloys under prolonged thermal exposure.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"932 ","pages":"Article 148272"},"PeriodicalIF":6.1,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759618","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":"Fatigue strength optimization of compacted graphite cast iron processed by austempering process","authors":"X.Y. Teng ,&nbsp;B.Z. Tan ,&nbsp;J.C. Pang ,&nbsp;Y. Chen ,&nbsp;C.L. Zou ,&nbsp;F. Shi ,&nbsp;S.X. Li ,&nbsp;Z.F. Zhang","doi":"10.1016/j.msea.2025.148271","DOIUrl":"10.1016/j.msea.2025.148271","url":null,"abstract":"<div><div>The fatigue property optimization of compacted graphite cast iron (CGI) by the austempering process was investigated. The austenitizing at 850 °C firstly then austempering at 280 °C and 370 °C respectively were selected. The tensile and fatigue properties and corresponding damage mechanism of the CGI and austempered CGI (ACGI) samples were carried out. The highest fatigue strength of 221 MPa for CGI materials was obtained by austempering at 370 °C. The fatigue strength decreases first and then increases in CGI and ACGI samples with the increase of austempering temperature. The general relation between the tensile and fatigue strength of CGI was further investigated. The corresponding physical significance in the relations was proposed based on the different defect morphologies in cast iron alloys, which provides implications for understanding the relation between metal fatigue and tensile strength and optimizing fatigue properties.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"932 ","pages":"Article 148271"},"PeriodicalIF":6.1,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768576","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":"Study on the forming limit of TA1 pure titanium foils based on digital image correlation: Experiments and predictive models","authors":"Peisheng Han ,&nbsp;Jixin Yang ,&nbsp;Fengyuan Yang ,&nbsp;Zixing Cheng ,&nbsp;Xiaogang Wang","doi":"10.1016/j.msea.2025.148267","DOIUrl":"10.1016/j.msea.2025.148267","url":null,"abstract":"<div><div>At the micro/mesoscopic scale, traditional macroscopic methods, theories, and models used to determine the forming limit are not entirely suitable, given the impact of the size effect on mechanical response, plastic deformation, and fracture. To accurately predict the failure of metal foils during microforming processes, taking into account the size effect on the forming limit. This study constructed tension-compression forming limit diagrams (FLD) for TA1 pure titanium (Ti) foils at thicknesses of 0.08 mm, 0.1 mm, and 0.2 mm based on digital image correlation (DIC). Specifically, it implemented Holmberg uniaxial tensile testing, model prediction based on the modified Oyane ductile fracture criterion, and the fully connected neural network (FCNN). It is found that the forming limit of TA1 pure Ti foils increases with larger specimen thickness. For foils of the same thickness, the forming limit rises with the decrease in the ratio of specimen thickness to grain size (t/d). Additionally, as t/d increases, the influence of the strain rate sensitivity on the overall strain state of the material diminishes, creating similar strain states of specimens in different strain paths. By analyzing the FLD constructed in three methods, it is found that with the t/d and Hill48 yield criteria, the modified Oyane ductile fracture criterion effectively predicted the size effect. After appropriate training, the FCNN model with optimal topology also achieved a high-accuracy prediction of the forming limit.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"932 ","pages":"Article 148267"},"PeriodicalIF":6.1,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143738854","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}