Materials Science and Engineering: A最新文献

{"title":"Influence of lamellar-α geometry characteristics on mechanical properties of bimodal microstructure in Ti-6Al-4V alloy","authors":"Honghui Li ,&nbsp;Erju Sun ,&nbsp;Ke Wang","doi":"10.1016/j.msea.2025.148018","DOIUrl":"10.1016/j.msea.2025.148018","url":null,"abstract":"<div><div>From a new perspective with considering the combined effect of coordination deformation and heterogeneous effect, this work investigates the influence of the geometric characteristics of lamellar α on the mechanical properties of TC4 titanium alloy. To this end, four types (I-IV) of bimodal microstructures with similar equiaxed α (α_eq) phase content but differing geometric characteristics of lamellar α were designed. In Types I and II, the lamellar α exhibited a colony structure, with Type I having thinner lamella α and smaller α-colony size than Type II. In Types III and IV, the lamellar α exhibited a bi-lamellar structure consisting of basketwave lamella and dispersed α, where Type III had thinner basketwave-α and more dispersed α than Type IV. The tensile test and loading-unloading-reloading (LUR) test results showed that Types I-IV microstructures exhibited significant differences in tensile properties and hetero-deformation induced (HDI) stress. Specifically, in Types I and II, Type I exhibited a higher strength than Type Ⅱ without sacrificing plasticity due to the formation of more α-colony/colony interfaces and enhanced HDI strain hardening. In Types III and IV, Type III exhibited a significantly higher strength than Type IV while maintaining good plasticity due to enhanced dispersion strengthening and HDI strain hardening. Additionally, it can be found that Types III and IV are more advantageous than Types I and II for the combination of strength and plasticity. It could be attributed to that bi-lamellar structure in Types III and IV fabricated multiple strong heterogeneous interfaces, which could promote the formation and accumulation of geometrically necessary dislocations (GNDs) to enhance HDI stress and heterogeneous effect.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"927 ","pages":"Article 148018"},"PeriodicalIF":6.1,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143421264","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":"Softening-resistant ultra-strong nanotwinned CoCrFeNi medium entropy alloy thin films","authors":"Jian-Jie Wang ,&nbsp;Cheng-Yuan Tsai ,&nbsp;Shou-Yi Chang ,&nbsp;King-Ning Tu ,&nbsp;Fan-Yi Ouyang","doi":"10.1016/j.msea.2025.147928","DOIUrl":"10.1016/j.msea.2025.147928","url":null,"abstract":"<div><div>Nanostructured and particularly nanotwinned metals with superior mechanical performance have been developed for decades but still suffer from the drawback of detwinning-caused significant softening at an elevated temperature or under mechanical stress, especially for those with a twin spacing below 10 nm. In the present work, we synthesized an ultra-strong nanotwinned CoCrFeNi medium entropy alloy thin films, with an average twin plane spacing of only 2 nm but an ultrahigh softening resistance. Overwhelming coarse-grained and nanocrystalline medium or high entropy alloys, or other nanotwinned metals, the nanotwinned CoCrFeNi medium entropy alloy thin films exhibited a much higher hardness of 11.3 GPa, particularly at a low temperature of −80 °C. A slight decrease in hardness for only 10 % was noticed at 300 °C, and very thin localized detwinning was observed only at the top surface of the nanoindenting deformation zone, attributable to the highly stabilized nanotwinned structure of the alloy in a consequence of its low stacking fault energy. In addition, in the detwinning region, high density of Lomer-Cottrell locks was observed in the high-temperature case, which also provides a significant ability against the softening. The present work demonstrates that the synergy of nanotwinning and distorted structure provides medium entropy alloy thin films ultrahigh structural and mechanical stabilities over a wide range of temperatures.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"927 ","pages":"Article 147928"},"PeriodicalIF":6.1,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143420425","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":"Friction surface layer deposition of triple-phase Al10Cr12Fe35Mn23Ni20 high entropy alloy: Process optimization and microstructural evolution","authors":"Mohan Sai Kiran Kumar Yadav Nartu ,&nbsp;David Garcia ,&nbsp;Subhashish Meher ,&nbsp;Tianhao Wang ,&nbsp;Jorge F. Dos Santos ,&nbsp;Isabella Van Rooyen","doi":"10.1016/j.msea.2025.148019","DOIUrl":"10.1016/j.msea.2025.148019","url":null,"abstract":"<div><div>A high-strength Co-free triple-phase Al₁₀Cr₁₂Fe₃₅Mn₂₃Ni₂₀ high-entropy alloy (HEA) was successfully fabricated using Friction Surface Layer Deposition (FSLD), a bulk manufacturing method. Multiple single-layer deposits were produced by varying forging force (F) and traverse speeds (T_r) to optimize the process parameters. The optimized conditions (F = 40 kN &amp; T_r = 200 mm/min) were then applied to manufacture a scaled-up multi-layer specimen. The initial microstructure of the HEA consisted of coarse grains of the soft FCC-phase, long columnar dendrites of the hard BCC-phase, and small precipitates of the harder B2-phase within the BCC-dendrites. During FSLD, the FCC-matrix underwent continuous dynamic recrystallization due to high-temperature severe plastic deformation, forming finer equiaxed grains. Simultaneously, the BCC-dendrites fractured into smaller fragments, some of which experienced partial growth and coarsening under applied stress, resulting in an hourglass morphology. In contrast, the small B2-precipitates within the BCC-fragments dissolved during the elevated temperatures of FSLD and reprecipitated as substantially finer precipitates during continuous cooling post-FSLD. Additionally, the orientation relationships between the FCC and BCC/B2 phases were completely destroyed by the severe thermoplastic deformation inherent to FSLD. The microstructural refinements led to a substantial improvement in hardness from 177 HV to 283 HV, driven by Hall-Petch strengthening. The increased number of interfaces, including coherent BCC-B2 interfaces, potentially enhances the sink strength and radiation tolerance of the HEA, making it a promising candidate for nuclear applications. This study also highlights FSLD as a versatile technique for achieving tunable properties in HEAs, with detailed schematics illustrating the complex mechanisms of phase transformations during processing.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"927 ","pages":"Article 148019"},"PeriodicalIF":6.1,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143377951","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 of the creep crack growth behavior of interface of a dissimilar weld between Alloy617 and 10Cr steels","authors":"Avinash Gopalan ,&nbsp;M. Nani Babu ,&nbsp;Chanchal Ghosh ,&nbsp;R. Mythili ,&nbsp;A. Moitra ,&nbsp;M. Vasudevan ,&nbsp;R. Divakar","doi":"10.1016/j.msea.2025.148008","DOIUrl":"10.1016/j.msea.2025.148008","url":null,"abstract":"<div><div>The creep crack growth (CCG) behavior of interface of alloy 617 M/10Cr ferritic steel dissimilar metal weld joint (DMWJ) has been evaluated at the operating temperature of 823K using compact tension (CT) specimens in accordance with the ASTM E1457standard. The initial pre-crack was placed in alloy 617 side of the interface and the final creep crack growth found to occur along the interface, predominantly along the 10Cr steel side. For quantitative evaluation, additional CCG tests were conducted on 10Cr steel and compared with the interface CCG rates. The CCG rate of the DMWJ interface was 10 times higher than that of 10Cr base at the C∗ value of 0.5 kJ/mm.h. The higher CCG rates of DMWJ are attributed to coarsening of carbide precipitates and softening of the matrix in addition to the physical, chemical and mechanical in-homogeneity across the interface. The mechanism of the CCG of the interface is associated with the creep cavitation, growth and coalescence ahead of the crack tip is confirmed by the microscopic examination.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"927 ","pages":"Article 148008"},"PeriodicalIF":6.1,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143395462","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":"Correlation of fatigue damage mechanisms with acoustic emissions in a titanium alloy having multiple main microtextures","authors":"Qianqian Tian ,&nbsp;Hongyun Luo ,&nbsp;Duoqi Shi","doi":"10.1016/j.msea.2025.147976","DOIUrl":"10.1016/j.msea.2025.147976","url":null,"abstract":"<div><div>This paper aims to investigate the correlation of fatigue damage mechanisms with acoustic emissions in a titanium alloy having multiple main microtextures. In the study, electron backscatter diffraction (EBSD) was used to analyze the texture state, the fatigue fracture characteristics were observed by scanning electron microscopy (SEM), and the dislocation morphology, length, and behavior during fatigue were analyzed by transmission electron microscopy (TEM). At the same time, AE was used to monitor the fatigue damage behavior of the alloy in real-time throughout the entire process. The results show that the fatigue life of the sample with multiple main textures is about 33 % lower than that of the main texture unitary sample. As for the characteristics of secondary cracks on the fracture surface, the average length and number density of secondary cracks are higher in the sample with multiple main textures, and not only the majority of secondary cracks are nearly parallel to the fatigue strip, but also a few micro-cracks are nearly perpendicular to the fatigue strip. This phenomenon is attributed to the existence of obvious orientation difference. The obvious orientation difference promotes the earlier dissociation of a larger number of grain boundary dislocations into Shockley partial dislocation pairs at the microscopic level, resulting in collective motion to form a small sliding step with a large number of secondary cracks. In addition, by analyzing and studying the correlation between fracture characteristics and AE characteristics, AE characterization of fracture characteristics at different crack propagation stages has been achieved, or the AE characterization method for fracture is found. It will contribute to the in-depth understanding of crack propagation mechanism in multi-texture alloys under fatigue condition.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"927 ","pages":"Article 147976"},"PeriodicalIF":6.1,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143420515","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":"Hot deformation behavior and deformation mechanism of γʹ strengthened Co-based superalloys","authors":"Xu Yang-tao ,&nbsp;Wei Jiang-long ,&nbsp;Xu bo ,&nbsp;Hu Haitao ,&nbsp;Nan Hong-qiang","doi":"10.1016/j.msea.2025.147932","DOIUrl":"10.1016/j.msea.2025.147932","url":null,"abstract":"<div><div>Hot tensile experiments were carried out using LE 5105 electronic universal testing machine to study the hot deformation behavior at temperatures of 900–990 °C and strain rates of 0.0001–0.0125s⁻¹. The results show that the peak flow stress decreases with increasing temperature and decreasing strain rate, and the flow curve of Co-7Al-7W superalloy belongs to the typical dynamic recrystallisation (DRX) type. The flow instability regions are 900 °C/0.0005s⁻¹ and 930–960 °C/0.0025–0.0125s⁻¹, the flow stability regions are 900 °C/0.0025s⁻¹-0.0125s⁻¹、960°C–990 °C/0.0001s⁻¹-0.0005s⁻¹. The instability regions is mainly composed of deformed grains, and as the temperature increases, most of the grains in the stable region are fine equiaxed recrystallized grain structures. The microstructure analysis of the Co-7Al-7W superalloy using EBSD reveals that the DRX nucleation mechanism of the Co-7Al-7W alloy is predominantly DDRX, with CDRX playing only an auxiliary role in nucleation. The presence of γʹ phase inhibits dislocation migration, delays DRX, and hinders nucleation and growth of recrystallized grains.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"927 ","pages":"Article 147932"},"PeriodicalIF":6.1,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143429382","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":"Thermal aging effect on elevated temperature deformation mechanisms of 316L stainless steel weld metal by small punch test","authors":"Y. Fan ,&nbsp;J.Y. Hu ,&nbsp;W.W. Bian ,&nbsp;Y. Hu ,&nbsp;K.X. Cui","doi":"10.1016/j.msea.2025.148005","DOIUrl":"10.1016/j.msea.2025.148005","url":null,"abstract":"<div><div>The effects of long-term thermal aging on the microstructural evolution and its elevated temperature deformation behavior of 316L stainless steel weld metal were studied using the small punch test at 350 °C. The mechanical responses at the microstructural scale were investigated to better understand the mechanism of the influence of long-term thermal aging on the mechanical properties of the 316L weld metal. The results indicated that the hardness and mechanical strength of the 316L weld metal increased slightly with extended thermal aging time at 400 °C, which was primarily attributed to spinodal decomposition and G-phase precipitation in the ferrite phase. The hardening of ferrite increased the deformation incompatibility between the ferrite and austenite phases. Slip bands were blocked at the phase interface, leading to preferential cracking along the phase interface. In contrast, in the as-received 316L weld metal, slip bands could extend between two phases by means of multi-system slip, and cracks tended to crack along austenite grain boundaries. Notably, the deformation mechanism of austenite phase exhibited significant changes due to long-term thermal aging. The as-received austenite deformed through dislocation slip and twinning due to its lower stacking fault energy. After long-term thermal aging, the primary mechanisms governing the plastic deformation of austenite shifted to cross slip and multiple slip. In addition, a smaller dislocation cell structure (about 200 nm) was formed in the deformed austenite after long-term thermal aging, compared to a larger dislocation cell structure (about 500 nm) in the deformed austenite before aging. In contrast, the deformation mechanism of the ferrite phase in the 316L weld metal remained consistent, dominated by slip deformation both before and after long-term thermal aging.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"927 ","pages":"Article 148005"},"PeriodicalIF":6.1,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143377955","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":"Exceptional creep resistance of additively manufactured 316L stainless steel via unprecedented early laves phase formation","authors":"Kwang-Hyeok Lim ,&nbsp;Jong-Soo Bae ,&nbsp;Shubham Chandra ,&nbsp;KenHee Ryou ,&nbsp;Pyuck-Pa Choi ,&nbsp;Xipeng Tan ,&nbsp;Gi-Dong Sim","doi":"10.1016/j.msea.2025.148006","DOIUrl":"10.1016/j.msea.2025.148006","url":null,"abstract":"<div><div>Additively manufactured (AM) 316L stainless steel (SS) has garnered significant interest due to its superior strength with moderate ductility, making it a promising material for vessels and pipelines in nuclear reactors. Given the long-term pressurized thermal exposure inherent in the nuclear reactor environments, enhancing the creep resistance and investigating the creep mechanism of AM 316L SS are crucial. This study presents the exceptional creep resistance of 316L SS fabricated by electron beam powder bed fusion (EB-PBF) and elucidates the underlying creep deformation mechanisms. High-temperature creep tests were conducted on EB-PBF 316L SS at 600 °C and 650 °C, with performance benchmarked against 316L SS reported in the literature. Remarkably, the creep life of EB-PBF 316L SS was found to be 15.4 times greater than that of laser-based powder bed fusion 316L SS at 650 °C, 225 MPa, and 3.6 times higher than that of conventional wrought 316L SS at 650 °C, 250 MPa. The exceptional creep properties are primarily attributed to the early formation of the coherent C14 Laves phase along the grain boundaries, which retards the formation of creep cavities by preventing grain boundary sliding and delaying the accumulation of dislocations.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"927 ","pages":"Article 148006"},"PeriodicalIF":6.1,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143377956","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 Ti on the Ageing Microstructure and Mechanical Properties of Ni-Co-Cr-Ti Multi-Principal Element Alloy","authors":"Yuxin Sun ,&nbsp;Caixia Wang ,&nbsp;Caijuan Shi ,&nbsp;Ruixin Sheng ,&nbsp;Weidong Li ,&nbsp;Gihan Velisa ,&nbsp;Shuying Chen ,&nbsp;Fanchao Meng ,&nbsp;Peter K. Liaw ,&nbsp;Y. Tong","doi":"10.1016/j.msea.2025.148007","DOIUrl":"10.1016/j.msea.2025.148007","url":null,"abstract":"<div><div>We investigated the impact of Ti addition on the microstructure, tensile properties, and deformation mechanisms of the Co₅₀Cr₃₀Ni₂₀ multi-principal element alloy. Our findings show that different heat treatments yield varied microstructures, including combinations of incoherent precipitates at grain boundaries with coherent precipitates within grains, mixtures of lamellae in discontinuous precipitation zones and coherent precipitates in continuous zones, and configurations of a Widmanstätten microstructure with cuboidal precipitates. Among all aged specimens, the strongest alloy exhibits a yield strength of 1193 MPa, ultimate tensile strength of 1535 MPa, and notable elongation of 17%. Detailed microstructural characterization reveals that Ti addition effectively suppresses the formation of the brittle hexagonal close-packed phase, while the uniform distribution of nanoscale L1₂ phase particles within grains contributes to grain refinement and dislocation pinning, enhancing alloy strength. Furthermore, the development of stacking fault networks introduces an additional strengthening mechanism via the dynamic Hall-Petch effect. Together, these mechanisms are essential for improving strain-hardening capacity and ultimately enhancing the alloy’s ductility.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"927 ","pages":"Article 148007"},"PeriodicalIF":6.1,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143377950","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":"Planar defect dominated ultra-high strength Cu-Sn-Ni alloy wires with single FCC structure prepared by cold drawing","authors":"Yinfei Ju ,&nbsp;Lichu Zhou ,&nbsp;Caijuan Shi ,&nbsp;Runguang Li ,&nbsp;Yu Wang ,&nbsp;Boqing Gao ,&nbsp;Yuhui Chen ,&nbsp;Jianqing Jiang ,&nbsp;Feng Fang","doi":"10.1016/j.msea.2025.148016","DOIUrl":"10.1016/j.msea.2025.148016","url":null,"abstract":"<div><div>Nickel bronze is provided with excellent wear and high strength, and it is widely applied to aerospace, electronics, machinery manufacturing, and communications. In this study, Cu-12Sn-2Ni alloy wires were facilitated by cold-drawn without intermediate annealing to a tensile strength of 1.3 GPa and a Vickers hardness of 425 HV. During the drawing process, the grains in Cu-12Sn-2Ni alloy are rapidly refined into nano fibers as a result of the interaction between prevailing plane defects, such as stacking faults and nano twins. Dense deformation twins are generated in the wires due to the alloy's low stacking fault energy of 18 mJ/m². When the strain reaches 3.22, the stacking fault probability and dislocation density increase to 7.6 % and 1.88 × 10¹⁵ m⁻², respectively. Dislocation strengthening and boundary strengthening are calculated to be 468.60 MPa and 781.40 MPa in the wire at the strain of 3.22. The fibrous grain boundaries are derived from a considerable proportion of twining indicating that the strength increment by planar defects such as SFs and twin boundaries occupies the crucial position on the Cu-Sn-Ni alloy. The investigation of the strengthening mechanism of the presented Cu-12Sn-2Ni alloy offers further guidance and understanding for ultra-high strength structural metals.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"927 ","pages":"Article 148016"},"PeriodicalIF":6.1,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143386819","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}