Intermetallics最新文献_第10页

Effects of extrusion temperature on the microstructure and mechanical properties of low-alloyed Mg-Bi-Ca-Mn alloy 挤压温度对低合金镁-铋-钙-锰合金微观结构和力学性能的影响

IF 4.3 2区材料科学

Intermetallics Pub Date : 2024-09-10 DOI: 10.1016/j.intermet.2024.108480

Weiying Huang , Yongheng Su , Kefu Gan , Jian Chen , Wei Qiu , Xiaojie Zhou , Qiang Yu , Liang Liang , Wei Chen , Libo Zhou

{"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>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 (Mg2Ca) 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.</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}

引用次数: 0

Machine learning assisted design of new ductile high-entropy alloys: Application to Al-Cr-Nb-Ti-V-Zr system 机器学习辅助设计新型韧性高熵合金：应用于 Al-Cr-Nb-Ti-V-Zr 系统

IF 4.3 2区材料科学

Intermetallics Pub Date : 2024-09-09 DOI: 10.1016/j.intermet.2024.108469

Denis Klimenko , Nikita Stepanov , Roman Ryltsev , Nikita Yurchenko , Sergey Zherebtsov

{"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>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 Al1Cr9Nb35Ti5V40Zr10 alloy demonstrates a combination of high strength at room and elevated temperature, combined with good ductility at room temperature.</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}

引用次数: 0

Effect of Cr addition on the formation of Fe-Al intermetallic phases in Al2O3/Fe-Al coatings 添加铬对 Al2O3/Fe-Al 涂层中铁铝金属间相形成的影响

IF 4.3 2区材料科学

Intermetallics Pub Date : 2024-09-07 DOI: 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>Al2O3/Fe-Al coatings are favored for their excellent comprehensive properties in nuclear fusion power applications. A critical step in fabricating Al2O3/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 Fe2Al5, 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.</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}

引用次数: 0

The effect of Hf addition on the precipitation hardening and dynamic softening behavior of NiTi alloy during hot deformation 添加 Hf 对热变形过程中镍钛合金沉淀硬化和动态软化行为的影响

IF 4.3 2区材料科学

Intermetallics Pub Date : 2024-09-06 DOI: 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>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−1. Under this condition, the microstructure of the alloy has a high DRX volume fraction and low average ρGND. 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.</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}

引用次数: 0

Tensile properties and deformation mechanisms of a fourth-generation nickel-based single crystal superalloy at intermediate temperatures 第四代镍基单晶超级合金在中温条件下的拉伸性能和变形机制

IF 4.3 2区材料科学

Intermetallics Pub Date : 2024-09-05 DOI: 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>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.</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}

引用次数: 0

The electrochemical behaviour of Ti-48Al-2Cr-2Nb produced by electron beam powder bed fusion process 电子束粉末床熔融工艺制备的 Ti-48Al-2Cr-2Nb 的电化学行为

IF 4.3 2区材料科学

Intermetallics Pub Date : 2024-09-05 DOI: 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>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.</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}

引用次数: 0

Microstructure and properties of typical equiatomic CrMnFeCoNi high entropy alloy doped with different rare earth elements 掺杂不同稀土元素的典型等原子铬锰铁钴镍高熵合金的显微结构和性能

IF 4.3 2区材料科学

Intermetallics Pub Date : 2024-09-05 DOI: 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>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 × 10−6 mm3 N−1 m−1, 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 CrMnFeCoNiSm0.2 alloy were 2.94 × 10−6 A cm−2 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.</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}

引用次数: 0

Low cycle fatigue and cycle hardening behavior of heterogeneous Ni2Co1Fe1V0.5Mo0.2 medium entropy alloy 异质 Ni2Co1Fe1V0.5Mo0.2 中熵合金的低循环疲劳和循环硬化行为

IF 4.3 2区材料科学

Intermetallics Pub Date : 2024-09-04 DOI: 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>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 Ni2Co1Fe1V0.5Mo0.2 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 Ni2Co1Fe1V0.5Mo0.2 MEA exhibits stronger strain hardening effect than that in CoCrFeMnNi HEA. In present work, the low-cycle fatigue behavior of the non-equiatomic Ni2Co1Fe1V0.5Mo0.2 MEA with heterogeneous grain structures was further investigated. The heterogeneous Ni2Co1Fe1V0.5Mo0.2 MEA exhibits high fatigue resistance at 0.25 % strain amplitude (51285 N), 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.</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}

引用次数: 0

Thermal stability and grain growth kinetics in rotary swaged Al0.35CoCrFeNi complex concentrated alloy 旋转压接 Al0.35CoCrFeNi 复合浓缩合金的热稳定性和晶粒生长动力学

IF 4.3 2区材料科学

Intermetallics Pub Date : 2024-09-04 DOI: 10.1016/j.intermet.2024.108456

Kateryna Ulybkina , Kateryna Kamyshnykova , Alena Klimová , Tatiana Pelachová , Andrea Školáková , Jan Pinc

{"title":"Thermal stability and grain growth kinetics in rotary swaged Al0.35CoCrFeNi complex concentrated alloy","authors":"Kateryna Ulybkina , Kateryna Kamyshnykova , Alena Klimová , Tatiana Pelachová , Andrea Školáková , Jan Pinc","doi":"10.1016/j.intermet.2024.108456","DOIUrl":"10.1016/j.intermet.2024.108456","url":null,"abstract":"<div>A complex concentrated alloy (CCA) with a nominal composition of Al0.35CoCrFeNi (mol.%) was prepared by vacuum induction melting and tilt casting. The microstructure of the alloy in the as-cast state consists of columnar dendritic grains. The ingots were solution annealed, rotary swaged, and heat treated to obtain a uniform fine-grain structure. To study the behavior of recrystallization and grain growth, heat treatment was carried out at temperatures from 1150 °C to 1300 °C and holding times up to 480 min. The resulting microstructures were analyzed by LM, SEM, TEM, EBSD, and XRD methods followed by a comparison with the results of hardness measurements. The alloy has a thermally stable single-phase face-centered cubic (FCC) structure in the studied temperature range. The grain growth kinetics were analyzed using classical models, and the activation energy was estimated to be ∼458 kJ mol−1 using an Arrhenius-type equation. The greatest resistance to grain growth was observed at a temperature of 1150 °C. Hardness tests demonstrated an almost double increase in hardness after swaging and a sharp drop during the following heat treatment due to the onset of recrystallization. The Hall-Petch hardening coefficient was calculated to be ∼277.5 HV μm−1/2.</div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"175 ","pages":"Article 108456"},"PeriodicalIF":4.3,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142136754","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}

引用次数: 0

Primary slip induced band-like structures and the associated recrystallization kinetics in Ti2AlNb alloy with centimeter-grade coarse grains 具有厘米级粗晶粒的 Ti2AlNb 合金中的原生滑移诱导带状结构及相关再结晶动力学

IF 4.3 2区材料科学

Intermetallics Pub Date : 2024-09-02 DOI: 10.1016/j.intermet.2024.108466

Zhongyuan Yang , Haiming Zhang , Yi Zhou , Risheng Qiu , Zhenshan Cui

{"title":"Primary slip induced band-like structures and the associated recrystallization kinetics in Ti2AlNb alloy with centimeter-grade coarse grains","authors":"Zhongyuan Yang , Haiming Zhang , Yi Zhou , Risheng Qiu , Zhenshan Cui","doi":"10.1016/j.intermet.2024.108466","DOIUrl":"10.1016/j.intermet.2024.108466","url":null,"abstract":"<div>Ti2AlNb alloy, as a highly promising superalloy in the aerospace ﬁeld, is limited by inferior workability due to centimeter-grade coarse grains formed through casting. An in-depth understanding of the relationship between deformation heterogeneities and recrystallization kinetics of the matrix B2 phase is critical to refine and optimize its microstructure. Plane strain compression followed by heat treatment, microstructure characterizations, and full-field crystal plasticity simulations were conducted. The research found that uniform primary-slips existed in most regions of the alloy. These regions exhibited negligible deformation stored energy and misorientation, and therefore, recrystallization cannot occur after heating. The observed slip transfer at grain boundaries with good geometric alignment also indicates the difficulty in dislocation pileup as the potential recrystallization site. Three typical band-like structures, i.e., transition band, slip-interlacing band, and shear band, formed by intersection and localization of slips, possessed high deformation stored energy. Cell-like substructures readily developed in the first two regions with intersecting slips, rather than in the shear band with parallel slips. As a result, many subgrains and unclosed boundaries were formed in the first two types of bands within grains after heating due to the significant recovery effect. These multilevel deformation heterogeneities were found to be strongly associated with the dislocation structure of the alloy. TEM observations found the dissociation of dislocations with narrow widths, which enhances dislocation mobility. Consequently, the primary-slip characteristic can be maintained at a relatively large deformation, and slip transfer can occur at grain boundaries where a good geometric alignment exists.</div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"174 ","pages":"Article 108466"},"PeriodicalIF":4.3,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142121635","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}

引用次数: 0