{"title":"Relationship between the entropy of mixing, excess entropy and the shear viscosity of metallic glasses near the glass transition","authors":"A.S. Makarov , J.B. Cui , J.C. Qiao , G.V. Afonin , N.P. Kobelev , V.A. Khonik","doi":"10.1016/j.intermet.2024.108478","DOIUrl":"10.1016/j.intermet.2024.108478","url":null,"abstract":"<div><p>We measured the shear viscosity of 14 metallic glasses (MGs) differing with their mixing entropy Δ<em>S</em><sub><em>mix</em></sub>. It is found that the viscosity at the glass transition temperature <em>T</em><sub><em>g</em></sub> significantly increases with Δ<em>S</em><sub><em>mix</em></sub>. Using calorimetric data, we calculated the excess entropy Δ<em>S</em> of all MGs with respect to their maternal crystalline states as a function of temperature. It is shown that the excess entropy Δ<em>S</em> both at room temperature and at <em>T</em><sub><em>g</em></sub> decreases with Δ<em>S</em><sub><em>mix</em></sub>. It is concluded that glasses with ‘high mixing entropy’ Δ<em>S</em><sub><em>mix</em></sub> correspond to MGs with low excess entropy Δ<em>S</em>. The origin of the increased shear viscosity at <em>T</em><sub><em>g</em></sub> of glasses with high Δ<em>S</em><sub><em>mix</em></sub> is determined by their reduced excess entropy Δ<em>S</em>.</p></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"175 ","pages":"Article 108478"},"PeriodicalIF":4.3,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142169488","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}
IntermetallicsPub Date : 2024-09-11DOI: 10.1016/j.intermet.2024.108481
Zhongfeng Chen , Anping Dong , Zhengye Zhang , Baode Sun , Yunwei Pan
{"title":"Temperature-dependent deformation mechanisms of γ′ phases in a newly developed NiCoCr-based superalloy","authors":"Zhongfeng Chen , Anping Dong , Zhengye Zhang , Baode Sun , Yunwei Pan","doi":"10.1016/j.intermet.2024.108481","DOIUrl":"10.1016/j.intermet.2024.108481","url":null,"abstract":"<div><p>The γ′-strengthened NiCoCr-based superalloys are extensively used in aerospace, energy, and chemical industries. This work focuses on tensile properties and evolution of deformation mechanism in a newly developed NiCoCr-based superalloy, designated K439B, at temperatures ranging from 25 °C to 1000 °C. The results demonstrate that the deformation mechanisms of this alloy are temperature-dependent. Slip bands and strongly-coupled dislocation pairs shear γ′ precipitates at 25 °C, resulting in high yield strength and work hardening rate. At 600 °C and 700 °C, the Lomer-Cottrell (L-C) locks are observed, and stacking faults shearing γ′ precipitates become the primary deformation mechanism. At temperatures reaching 800 °C, the yield strength exhibits an anomalous increase originating from the formation of Kear-Wilsdorf (K-W) locks. When the temperature exceeds 800 °C, the primary deformation mechanism is transformed into dislocations bypassing γ′ through the Orowan mechanism. The present study elucidates the deformation mechanism of this novel designed superalloy, thereby furnishing a theoretical foundation for the further development of the alloy system.</p></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"175 ","pages":"Article 108481"},"PeriodicalIF":4.3,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142169489","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 extrusion temperature on the microstructure and mechanical properties of low-alloyed Mg-Bi-Ca-Mn alloy","authors":"Weiying Huang , Yongheng Su , Kefu Gan , Jian Chen , Wei Qiu , Xiaojie Zhou , Qiang Yu , Liang Liang , Wei Chen , Libo Zhou","doi":"10.1016/j.intermet.2024.108480","DOIUrl":"10.1016/j.intermet.2024.108480","url":null,"abstract":"<div><p>A new rare earth-free low-alloyed Mg-0.5Bi-0.8Ca-0.8Mn (wt.%) alloy was prepared at three extrusion temperatures (225, 250 and 275 °C). The effects of low-temperature extrusion on the microstructure and mechanical properties of the alloy were studied. Experimental results show that the dynamic recrystallization (DRX) grains are significantly refined by low-temperature extrusion, and the dynamic recrystallization process is further delayed by the Mn precipitate phase, resulting in a bimodal structure composed of ultrafine DRXed grains and coarse undynamic recrystallized (unDRXed) regions. At an extrusion temperature of 225 °C, the grain size was significantly refined, with an average DRXed grain size of 0.84 μm and a tensile yield strength of 418 MPa. Compared with other extruded magnesium alloys, the ultra-fine DRXed grains, strong basal fiber texture, high Schmid Factors of pyramidal <c + a> slip in the unDRXed regions, and along with a certain amount of second phase (Mg<sub>2</sub>Ca) distributed along the grain boundaries and nano-Mn particles uniformly distributed in the matrix, are the main reasons for the strength enhancement of low-temperature extruded magnesium alloys. The orientation of the DRXed grains in the alloy after extrusion at 250 °C is more random, which improves ductility. In addition, when the extrusion temperature reaches 275 °C, the alloy shows a fully recrystallized structure and exhibits rare earth (RE)-texture, obtaining high ductility but decreasing strength. This study provides a new idea for the development of high-strength Mg-Bi-based magnesium alloys by adjusting the extrusion temperature and alloying elements. This new high-strength and low-alloyed Mg-Bi-based alloy will help to enrich the series of high-performance, rare-earth free, low-cost extruded Mg alloy with certain application prospects.</p></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"175 ","pages":"Article 108480"},"PeriodicalIF":4.3,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142164049","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":"Machine learning assisted design of new ductile high-entropy alloys: Application to Al-Cr-Nb-Ti-V-Zr system","authors":"Denis Klimenko , Nikita Stepanov , Roman Ryltsev , Nikita Yurchenko , Sergey Zherebtsov","doi":"10.1016/j.intermet.2024.108469","DOIUrl":"10.1016/j.intermet.2024.108469","url":null,"abstract":"<div><p>The search for new high-entropy alloys (HEAs) with desired properties is an urgent problem that is hardly solvable experimentally due to the extremely large number of possible alloy compositions. Thus, methods for theoretical prediction of HEA's properties play a key role. Currently, effective predictive models are based on machine learning methods and modern data analysis algorithms. Here we address developing data-driven machine learning models (DDML) to predict the ductility of HEAs. We have built several DDMLs and found that the best approach is based on the Support Vector Classifier, which significantly outperforms phenomenological models (balanced accuracy of 0.784 and F-score of 0.824). By combining this model with a previously developed yield strength prediction model, we have predicted and fabricated novel HEAs of the Al-Cr-Nb-Ti-V-Zr system with good mechanical properties. An obtained Al<sub>1</sub>Cr<sub>9</sub>Nb<sub>35</sub>Ti<sub>5</sub>V<sub>40</sub>Zr<sub>10</sub> alloy demonstrates a combination of high strength at room and elevated temperature, combined with good ductility at room temperature.</p></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"175 ","pages":"Article 108469"},"PeriodicalIF":4.3,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142157547","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}
IntermetallicsPub Date : 2024-09-07DOI: 10.1016/j.intermet.2024.108475
Feilong Yang, Xin Xiang, Chang'an Chen, Ce Ma, Li Hu, Guikai Zhang, ChunLi Jiang, Tao Tang
{"title":"Effect of Cr addition on the formation of Fe-Al intermetallic phases in Al2O3/Fe-Al coatings","authors":"Feilong Yang, Xin Xiang, Chang'an Chen, Ce Ma, Li Hu, Guikai Zhang, ChunLi Jiang, Tao Tang","doi":"10.1016/j.intermet.2024.108475","DOIUrl":"10.1016/j.intermet.2024.108475","url":null,"abstract":"<div><p>Al<sub>2</sub>O<sub>3</sub>/Fe-Al coatings are favored for their excellent comprehensive properties in nuclear fusion power applications. A critical step in fabricating Al<sub>2</sub>O<sub>3</sub>/Fe-Al tritium-resistant coatings via “aluminizing + oxidation” method is the formation of Fe-Al intermetallic layer on the substrate surface at high temperatures. The present work aims to investigate the influence of chromium (Cr), a prevalent alloying element in Fe-base alloys (such as austenitic stainless steels, RAFM steels) used in fusion reactors, on the formation of Fe-Al intermetallic layers. The Fe-Al phase composition and microstructure of Fe-Cr alloys with different Cr content (0, 9, 19 wt%) were investigated by combinations of X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results indicate that Cr significantly influences the phase structure and microstructure of Fe-Al intermetallic layers, despite minimal effects on its overall thickness. Cr exists in the form of Cr-rich second phase in Fe<sub>2</sub>Al<sub>5</sub>, which reduces the transformation rate of an aluminum-rich phase to an iron-rich phase, and also delays the generation of zigzag- or tongue-shaped structure between the intermetallic layer and the substrate, resulting in the formation of a smooth interface.</p></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"175 ","pages":"Article 108475"},"PeriodicalIF":4.3,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142149034","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}
IntermetallicsPub Date : 2024-09-06DOI: 10.1016/j.intermet.2024.108474
Chengchuang Tao , Ge Zhou , Hongjun Huang , Bowen Zheng , Xiaojiao Zuo , Lijia Chen , Xiaoguang Yuan
{"title":"The effect of Hf addition on the precipitation hardening and dynamic softening behavior of NiTi alloy during hot deformation","authors":"Chengchuang Tao , Ge Zhou , Hongjun Huang , Bowen Zheng , Xiaojiao Zuo , Lijia Chen , Xiaoguang Yuan","doi":"10.1016/j.intermet.2024.108474","DOIUrl":"10.1016/j.intermet.2024.108474","url":null,"abstract":"<div><p>Nanoindentation test, high-temperature compression test, SEM, EBSD, and TEM observations are performed to investigate the effects of Hf additions on the microstructure and properties of NiTi alloy. The high-temperature deformation behavior of NiTi-8/12Hf alloys is discussed. The constitutive model and hot processing map are constructed, and the optimal processing interval of the two alloys is predicted. The results show that the content and size of precipitates increase with the addition of Hf. The nanoindentation hardness of the matrix with different Hf content increased from 3.36 ± 0.11 GPa to 5.47 ± 0.13 GPa. The main strengthening mechanism of the addition of the Hf to improve the strength is the solid solution strengthening effect and the load transfer effect. With the addition of 8 wt% and 12 wt% Hf, the instability areas are expanded. The optimal processing area of 8/12Hf alloys are 900 °C, 0.01s<sup>−1</sup>. Under this condition, the microstructure of the alloy has a high DRX volume fraction and low average ρ<sub>GND</sub>. As hot deformation progresses, the accumulated energy inside the alloy increases, leading to the activation of dislocations and the formation of more DDRX at grain boundaries. Dislocations within the grains aggregate to form LAGBs. The softening mechanism of 56Ni-Ti-8/12Hf alloy are DDRX and dynamic recover.</p></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"175 ","pages":"Article 108474"},"PeriodicalIF":4.3,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142149033","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}
IntermetallicsPub Date : 2024-09-05DOI: 10.1016/j.intermet.2024.108471
Shida Huo , Xinguang Wang , Zihao Tan , Yongmei Li , Yan Tao , Chunhua Zhang , Song Zhang , Xipeng Tao , Yunling Du , Yanhong Yang , Jide Liu , Jinlai Liu , Jinguo Li , Yizhou Zhou , Xiaofeng Sun
{"title":"Tensile properties and deformation mechanisms of a fourth-generation nickel-based single crystal superalloy at intermediate temperatures","authors":"Shida Huo , Xinguang Wang , Zihao Tan , Yongmei Li , Yan Tao , Chunhua Zhang , Song Zhang , Xipeng Tao , Yunling Du , Yanhong Yang , Jide Liu , Jinlai Liu , Jinguo Li , Yizhou Zhou , Xiaofeng Sun","doi":"10.1016/j.intermet.2024.108471","DOIUrl":"10.1016/j.intermet.2024.108471","url":null,"abstract":"<div><p>This paper comprehensively explores the causes of intermediate-temperature brittleness of a fourth-generation Nickel-based single-crystal superalloy through a systematic study of tensile properties and deformation mechanisms at intermediate-temperatures. The research was performed at temperature of 700 °C, 800 °C, 850 °C and 900 °C. The experimental alloy demonstrated the highest yield strength of 914 MPa and worst plasticity at 800 °C. It was found that pure-shearing fracture occurred at 700 °C and 800 °C, while the fracture characteristics of shear fracture and ductile fracture were found at 850 °C and 900 °C. Then, the slip bands extended in the same direction at 700 °C and 800 °C. The phenomenon was different at 850 °C and 900 °C. These deformation traces extended in the different directions. At 700 °C and 800 °C, the partial dislocation with Burgers Vector of a/3 <112> shearing into the γ′ phases was the predominate deformation mechanism, while both the partial dislocation with Burgers Vector of a/3 <112> and the super-dislocation with Burgers Vector of a <110> and a <010> shearing into the γ′ phases were present at 850 °C and 900 °C. Nevertheless, the mechanism of the super-dislocation with Burgers Vector of a <110> and a <010> shearing γ′ phases pervaded in the alloy at 900 °C. In general, it was concluded that the alloy underwent intermediate-temperature brittleness at 800 °C in terms of the changes of fracture features, slip bands and dislocation configurations. The results of this study provided an experimental reference and guidance for improving the safe serviceability of the fourth-generation single crystal superalloy.</p></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"175 ","pages":"Article 108471"},"PeriodicalIF":4.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142149116","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}
IntermetallicsPub Date : 2024-09-05DOI: 10.1016/j.intermet.2024.108472
Amir behjat, Abdollah Saboori, Manuela Galati, Luca Iuliano
{"title":"The electrochemical behaviour of Ti-48Al-2Cr-2Nb produced by electron beam powder bed fusion process","authors":"Amir behjat, Abdollah Saboori, Manuela Galati, Luca Iuliano","doi":"10.1016/j.intermet.2024.108472","DOIUrl":"10.1016/j.intermet.2024.108472","url":null,"abstract":"<div><p>Titanium aluminides (TiAl) are distinguished by their exceptional strength-to-weight ratio, making them ideal for aerospace and medical applications. Notably, TiAl alloys offer a unique combination of high-temperature resistance and corrosion resilience, contributing to their growing prominence in advanced engineering and biomedical fields. Although initially developed for aerospace applications, TiAl alloys have demonstrated promising potential as implant materials over time. Hence, this research focuses on producing γ-TiAl alloy through electron beam powder bed fusion (EB-PBF) technology, utilising a powder with a composition of Ti-48Al-2Cr-2Nb. For comparative purposes, the corrosion characteristics of Ti6Al4V produced via EB-PBF were also evaluated under identical conditions. The findings indicate that the EB-PBF γ-TiAl exhibits exceptional resistance to corrosion. This is supported by the significantly high polarisation resistance and corrosion potential values, as well as the notably low corrosion current value. However, based on the analysis of the polarisation and impedance curves, it can be observed that the γ-TiAl sample displayed a less protective passive film formation. This occurrence can be attributed to the presence of aluminium ions within the passive layer, resulting in the formation of unstable oxides. As a consequence, it can be inferred that γ-TiAl exhibits inferior resistance to pitting corrosion when compared to Ti6Al4V alloy. The point defect model and Mott-Schottky test further revealed that the γ-TiAl alloy exhibited increased oxygen vacancies. Additionally, the presence of aluminium ions as impurities or dopants led to their substitution for titanium ions, creating cationic vacancies within the passive film. The accumulation of excessive cation vacancies ultimately led to the initiation of pitting corrosion.</p></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"175 ","pages":"Article 108472"},"PeriodicalIF":4.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0966979524002917/pdfft?md5=4a36388d7a8693ea2a1eeeb489815b66&pid=1-s2.0-S0966979524002917-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142149094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
IntermetallicsPub Date : 2024-09-05DOI: 10.1016/j.intermet.2024.108477
Long Meng , Sheng Fang , Mingtian Tan , Wanying Fu , Lingsheng Ke
{"title":"Microstructure and properties of typical equiatomic CrMnFeCoNi high entropy alloy doped with different rare earth elements","authors":"Long Meng , Sheng Fang , Mingtian Tan , Wanying Fu , Lingsheng Ke","doi":"10.1016/j.intermet.2024.108477","DOIUrl":"10.1016/j.intermet.2024.108477","url":null,"abstract":"<div><p>The addition of rare earth elements (REEs) can effectively modify the microstructure of alloy and improve the properties. The effects of doping REEs in equiatomic CrMnFeCoNi high entropy alloys were investigated. Doping with REEs led to the formation of a few new phases enriched in the interdendritic regions and reduced the grain size. Doping REEs significantly improved the hardness and wear resistance of the alloy, and the Sm-doped alloy showed the most notable enhancement with the hardness value, the average friction coefficient and wear rate of HV 347.9, 0.28 and 0.91 × 10<sup>−6</sup> mm<sup>3</sup> N<sup>−1</sup> m<sup>−1</sup>, respectively. The mechanical properties of the alloy were improved by the second phase strengthening and grain refinement and the wear mechanism was typical abrasive wear. However, the electrochemical properties indicated that doping with REEs weakened the corrosion resistance of the alloys; Pr- and La-doped alloys altered the corrosion behaviors on the alloy surfaces. The self-corrosion current density and potential of CrMnFeCoNiSm<sub>0.2</sub> alloy were 2.94 × 10<sup>−6</sup> A cm<sup>−2</sup> and -0.46 V, respectively. This research plays a guiding role to study in REEs doping in HEA, meanwhile is of great significance in promoting the industrial application of HEA.</p></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"175 ","pages":"Article 108477"},"PeriodicalIF":4.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142149093","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}
IntermetallicsPub Date : 2024-09-04DOI: 10.1016/j.intermet.2024.108473
Wei Jiang , Heng Wang , Yonghao Zhao
{"title":"Low cycle fatigue and cycle hardening behavior of heterogeneous Ni2Co1Fe1V0.5Mo0.2 medium entropy alloy","authors":"Wei Jiang , Heng Wang , Yonghao Zhao","doi":"10.1016/j.intermet.2024.108473","DOIUrl":"10.1016/j.intermet.2024.108473","url":null,"abstract":"<div><p>Low-cycle fatigue behavior of high-entropy alloy (HEAs) and medium-entropy alloys (MEAs) have rarely been reported in literature though it is critical for industrial applications. In our previous work, a non-equiatomic Ni<sub>2</sub>Co<sub>1</sub>Fe<sub>1</sub>V<sub>0.5</sub>Mo<sub>0.2</sub> MEA was designed by adding V and Mo elements with bigger atomic size to heighten solution strengthening effect. Due to larger atomic size mismatch and more severe lattice distortion, the Ni<sub>2</sub>Co<sub>1</sub>Fe<sub>1</sub>V<sub>0.5</sub>Mo<sub>0.2</sub> MEA exhibits stronger strain hardening effect than that in CoCrFeMnNi HEA. In present work, the low-cycle fatigue behavior of the non-equiatomic Ni<sub>2</sub>Co<sub>1</sub>Fe<sub>1</sub>V<sub>0.5</sub>Mo<sub>0.2</sub> MEA with heterogeneous grain structures was further investigated. The heterogeneous Ni<sub>2</sub>Co<sub>1</sub>Fe<sub>1</sub>V<sub>0.5</sub>Mo<sub>0.2</sub> MEA exhibits high fatigue resistance at 0.25 % strain amplitude (51285 <em>N</em>), attributed to the pronounced dislocation planar slip and formation of stacking faults. At 0.3 % and 0.5 % strain amplitudes, dislocation interactions (including tangles and microbands) induced by extensive dislocation cross-slip result in obvious cyclic hardening but reduced lifetime. The findings assess the effect of solid solution strengthening on the fatigue behavior of MEAs. The fatigue cracks form either along slip bands in large grains or grain boundaries of small grains.</p></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"175 ","pages":"Article 108473"},"PeriodicalIF":4.3,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142136796","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}