Materials Science and Engineering: A最新文献

{"title":"Design and characterisation of new low-alloyed alumina forming ferritic/martensitic steels","authors":"F. Masari ,&nbsp;Rebeca Hernández ,&nbsp;M. Serrano ,&nbsp;J.M. Torralba ,&nbsp;M. Campos","doi":"10.1016/j.msea.2024.147598","DOIUrl":"10.1016/j.msea.2024.147598","url":null,"abstract":"<div><div>New efficient energy generation systems require materials capable of withstanding aggressive environments. The Cr-rich oxides formed by commercial stainless steels are not protective enough, so alumina (Al₂O₃) forming steels such as alumina-forming austenitic (AFA) steels and FeCrAl have been proposed as possible materials. However, they are prone to irradiation swelling or exhibit poor creep resistance. This study aims to develop a new kind of alloy, an Alumina Forming Ferritic-Martensitic steel, which combines the superior oxidation resistance from an alumina scale with the creep and irradiation swelling resistance of a martensitic structure. Thermodynamic simulations guided the alloy design of five Fe-Cr-Ni-Al compositions through a powder metallurgy route, ending with Spark Plasma Sintering of solid samples. EBSD and TEM analysis of the samples showed martensite in 4 out of the 5 sintered alloys, with various levels of retained austenite or ferrite in their structures. Tensile and small punch tests from room temperature to 500 °C demonstrated comparable mechanical properties to other AFA steel and to T91 and 316L, candidate materials for nuclear applications. After exposure to air at 800 °C for 500 h, the designed alloys formed protective aluminium oxide scales with corrosion rates similar to 316L and orders of magnitude better than T91. The results show that the developed alloys are promising for components subjected to aggressive environments and elevated temperatures.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"922 ","pages":"Article 147598"},"PeriodicalIF":6.1,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142758763","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}

{"title":"Overcoming the strength-ductility trade-off in zirconium using twin boundary engineering","authors":"G. Bharat Reddy ,&nbsp;Rajeev Kapoor ,&nbsp;Ayan Bhowmik ,&nbsp;Apu Sarkar ,&nbsp;Bhupendra K. Kumawat ,&nbsp;Sanjay Raj","doi":"10.1016/j.msea.2024.147602","DOIUrl":"10.1016/j.msea.2024.147602","url":null,"abstract":"<div><div>Tailoring the strength and ductility of metals through microstructural design has been a longstanding endeavour. Here, we report the development of a hierarchical ultrafine twinned microstructure in zirconium <em>via</em> a novel multi-axial cryo-forging (MACF) process. MACF of Zr resulted in the formation of dense and fine tensile twins, <span><math><mo>{</mo><mrow><mn>10</mn><mover><mn>1</mn><mo>¯</mo></mover><mn>2</mn></mrow><mo>}</mo><mo>&lt;</mo><mrow><mn>10</mn><mover><mn>1</mn><mo>¯</mo></mover><mn>1</mn></mrow><mo>&gt;</mo></math></span> (T-1) and <span><math><mrow><mrow><mo>{</mo><mrow><mn>11</mn><mover><mn>2</mn><mo>‾</mo></mover><mn>1</mn></mrow><mo>}</mo></mrow><mrow><mo>⟨</mo><mrow><mover><mn>1</mn><mo>‾</mo></mover><mover><mn>1</mn><mo>‾</mo></mover><mn>26</mn></mrow><mo>⟩</mo></mrow></mrow></math></span> (T-2) within coarse and equiaxed grains. This microstructure exhibited a remarkable combination of enhanced strength, strain-hardening rate, and ductility, compared to its coarse-grained counterpart. The yield strength and ultimate tensile strength increased by up to 26 % and 30 %, respectively, without compromising material ductility. The improved strength and strain-hardening stemmed from the activation of the harder &lt;c+a&gt; slip system and its consequent interaction with the fine twin boundaries. Notably, the growth of fine T-2 twins during ambient temperature deformation, absent in coarse-grained zirconium, contributed to additional ductility. Crystal plasticity simulations reveal that the activity of pyramidal &lt;c+a&gt; slip within T-2 twins is twice that of prismatic &lt;a&gt; slip, leading to an enhanced strain-hardening rate contributed by the T-2 twins. Subsequent heat treatment of MACF Zr at 500 °C relieved the elastic distortions around twin boundaries, and hence tensile straining led to stress-assisted easier migration of pre-existing twin boundaries. This resulted in a lowering of the strain-hardening rates. It was shown that the dislocation substructure around these typically incoherent tensile twins in hcp metals plays a crucial role in their strain-hardening behaviour.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"921 ","pages":"Article 147602"},"PeriodicalIF":6.1,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142757113","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":"Impression creep of a cast Ag-doped AZ91 magnesium alloy","authors":"A. Allami,&nbsp;A.R. Geranmayeh,&nbsp;R. Mahmudi","doi":"10.1016/j.msea.2024.147599","DOIUrl":"10.1016/j.msea.2024.147599","url":null,"abstract":"<div><div>The impact of 0.5 wt% silver (Ag) addition on the creep performance of the as-cast AZ91 Mg alloy was examined through impression creep tests under stresses between 175 and 700 MPa and temperatures in the range 425–525 K. It was found that creep rates were reduced at all temperatures and stress levels following Ag addition. This improvement in creep resistance can be ascribed to a combination of microstructural modification along with reduction and a more homogenous dispersion of the <em>β</em>-Mg₁₇Al₁₂ intermetallic phase. The effect of Ag on solid solution strengthening, the tendency of Ag atoms to abide on the <em>β</em>-Mg₁₇Al₁₂ phase, and the emergence of the thermally stable Mg₄Ag particles are regarded as other influential factors. These consequences indicate that Ag is an advantageous alloying element for enhancing high-temperature creep behavior of AZ91 alloy. The creep stress exponents and activation energies acquired for the alloys under investigation were in the range 4.9–6.2 and 92–125 kJ/mol, respectively. The observed reduction in creep activation energy with rising stress levels indicates the competition between two distinct creep mechanisms, namely dislocation climb governed by pipe and lattice diffusion; the former mechanism dominates at high stress levels, while the latter is predominant at lower stress levels.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"921 ","pages":"Article 147599"},"PeriodicalIF":6.1,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142743724","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":"Implementation of miniature tensile specimens in mechanical properties assessment of directed energy deposited Ti-6Al-4V: As-built and heat treated","authors":"Saeid Alipour ,&nbsp;Sung-Heng Wu ,&nbsp;Frank Liou ,&nbsp;Arezoo Emdadi","doi":"10.1016/j.msea.2024.147593","DOIUrl":"10.1016/j.msea.2024.147593","url":null,"abstract":"<div><div>Within the last two decades, additive manufacturing (AM), a. k.a. 3D printing, has provided promising solutions for producing near-net-shape components with intricate geometries. From the material perspective, titanium alloys, one of humankind's most essential structural materials, are being considered the first candidate for AMed parts due to their unique characteristics in strength-weight-corrosion combinations. However, measuring the mechanical properties of designed geometry remains a challenge due to the ineffectiveness of conventional standard tensile specimens in assessing the site-specific and intricate geometries. In AM, the current approach often consists of evaluating standard-sized samples with the assumption that components with complex geometries possess comparable mechanical properties, even though they may have undergone different thermal processes in various situations. Hence, combining the microstructural characterization, this study aims to investigate the mechanical properties of direct energy deposition (DED) Ti-6Al-4V through a newly designed miniature tensile test (M-TT) specimen. The as-built specimen showed ultimate tensile strength (UTS) of ∼1305.3 MPa and elongation of ∼8.6 % with the mixed basketweave and α-colony microstructure. However, the DED Ti-6Al-4V specimen heat-treated at 850 °C exhibited the highest average elongation of ∼13.2 % and decent UTS of ∼1240.3 MPa with the α+β microstructure.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"921 ","pages":"Article 147593"},"PeriodicalIF":6.1,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142743720","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":"Directed energy deposited Fe36Ni35Al17Cr10Mo2 eutectic high entropy alloy: Hierarchical microstructure and tensile properties","authors":"Dingcong Cui ,&nbsp;Zishu Chai ,&nbsp;Kexuan Zhou ,&nbsp;Meijuan Li ,&nbsp;Dongfeng Chen ,&nbsp;Jieguang Huang ,&nbsp;Xindang He ,&nbsp;Zhijun Wang ,&nbsp;Feng He","doi":"10.1016/j.msea.2024.147594","DOIUrl":"10.1016/j.msea.2024.147594","url":null,"abstract":"<div><div>Eutectic high entropy alloy (EHEA) has attracted much attention due to its outstanding properties, which are commonly fabricated through conventional manufacturing methods. Additive manufacturing (AM) techniques that can create near-net components provide opportunities for rapid prototyping EHEAs. This study elucidated the microstructural evolution mechanisms of Fe₃₆Ni₃₅Al₁₇Cr₁₀Mo₂ EHEA fabricated by directed energy deposition (DED) via XRD, SEM, and EBSD. The dual-phase dendrite structure, micro-scale heterogeneous grains, and nano-scale BCC phases collectively formed the hierarchical microstructure in the DEDed alloy. We used neutron diffraction to demonstrate texture components and their relation to mechanical behaviors. {013}&lt;100&gt; texture possesses the highest Schmid factor compared to other textures, causing texture-induced softening of the FCC and B2 phases during tension. {233}&lt;0 <span><math><mrow><mover><mn>1</mn><mo>‾</mo></mover></mrow></math></span> 1&gt; texture exhibits the low SF and hard orientation for the B2 phase. Due to the synergistic plastic deformation between FCC and B2 phases and precipitation strengthening from the BCC phases, the DEDed Fe₃₆Ni₃₅Al₁₇Cr₁₀Mo₂ exhibits an ultimate strength of ∼1267 MPa with an elongation of ∼20.1 % at room temperature. Moreover, the elevated-temperature tensile testing and crack analysis were employed to indicate the elevated-temperature fracture behaviors. We found that the nucleation and propagation of microcracks were suppressed at the phase boundary at elevated temperatures, avoiding brittleness and achieving excellent high-temperature mechanical properties. These results are expected to open ever-bright prospects for additive manufacturing Co-free high-performance EHEAs.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"921 ","pages":"Article 147594"},"PeriodicalIF":6.1,"publicationDate":"2024-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142722795","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":"Tensile behavior of Cu–35Zn (wt%) α-brass alloy at liquid helium temperature","authors":"Seon-Keun Oh ,&nbsp;Jun Ho Lee ,&nbsp;Seong-June Youn,&nbsp;Seung-Min Jeon,&nbsp;Jee Hyuk Ahn,&nbsp;Young-Kyun Kim,&nbsp;Young-Sang Na","doi":"10.1016/j.msea.2024.147587","DOIUrl":"10.1016/j.msea.2024.147587","url":null,"abstract":"<div><div>To evaluate the reliability of the mechanical properties of <em>α</em>-brass Cu–35Zn (wt%) alloys at extremely low temperatures, we performed tensile tests at 298, 77, and 4.2 K with an initial strain rate of 1 × 10⁻³ s⁻¹. Results showed that the yield strength, ultimate tensile strength, and tensile elongation increased as the tensile temperature decreased. Moreover, only two tensile curves obtained at 298 and 4.2 K exhibited a serrated flow. The serrations appearing at 298 K were caused by dynamic strain aging based on the interaction between diffusible Zn solute atoms and mobile dislocations, whereas those appearing at 4.2 K resulted from mechanical instability based on the edge dislocation avalanche. The increasing tensile strength with a decreasing tensile temperature originated from a combination of four different factors: 1) an increase in the yield strength because of a rise in the Peierls–Nabarro stress; 2) increases in the dislocation densities because of the suppression of dynamic recovery; 3) an increase in the number of dislocation structures due to the changes in the dislocation density and slip planarity; 4) an increase in the number of mechanical twins owing to the higher given tensile strength and lower stacking fault energy. The increase in tensile elongation with a decreasing tensile temperature was caused by the more aggressive formation of mechanical twins and dislocation structures, which caused a delay in stress localization. This aggressive formation also resulted in a finer and denser dimple morphology with a decreasing tensile temperature.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"921 ","pages":"Article 147587"},"PeriodicalIF":6.1,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142757111","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}

{"title":"Influence of spinning on the microstructure and mechanical properties of AZ91 alloy tubes","authors":"Zhong-sen Huang ,&nbsp;Kun-kun Deng ,&nbsp;Cui-ju Wang ,&nbsp;Kai-bo Nie ,&nbsp;Quan-xin Shi ,&nbsp;Hong-lei Liu ,&nbsp;Chang-zhen Jia","doi":"10.1016/j.msea.2024.147581","DOIUrl":"10.1016/j.msea.2024.147581","url":null,"abstract":"<div><div>After being subjected to spinning, the evolution of microstructure, texture, mechanical properties of the AZ91 alloy tube during the spinning process was investigated in the present work. The research results indicate that the grains of the AZ91 alloy are significantly refined after spinning. Moreover, a notable grain size difference appears between the inner and outer layers. As the spinning process proceeds, the efficiency of grain refinement in the inner is gradually enhanced, resulting in a reduction in the grain size difference between the inner and outer. The C-axis rotates along RD in the majority of the grains during spinning, resulting in a strong basal texture in the AZ91 alloy tube. Nevertheless, the texture intensity initially increases and then decreases as the spinning process continues. Spinning endows the AZ91 alloy tube with better mechanical properties, the ultimate tensile strength and elongation of which can reach 300 MPa and 13.5 %, respectively, at a spinning deformation of 69 %.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"921 ","pages":"Article 147581"},"PeriodicalIF":6.1,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142722920","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":"Excellent strength-ductility synergy in oxide dispersion strengthened AlCrFeNi high-entropy composites by heterostructure strategy","authors":"Xiaolong Li,&nbsp;Zheng Lu,&nbsp;Dingbo Sun,&nbsp;Shang Gao","doi":"10.1016/j.msea.2024.147590","DOIUrl":"10.1016/j.msea.2024.147590","url":null,"abstract":"<div><div>Oxide dispersion strengthened (ODS) AlCrFeNi high-entropy composites were produced by different heterostructure strategies to achieve strength and ductility synergy. The effects of different reinforcement types, reinforcement contents and oxide-forming elements in the matrix on the microstructure and mechanical properties of ODS-AlCrFeNi composites were investigated. The results showed that in the composites with different reinforcement types (ternary ODS-CrFeNi, quaternary ODS-CoCrFeNi and quinary ODS-CoCrFeNiMn), spinodal decomposition is observed in the all reinforcements, resulting in the formation of ellipsoidal/cuboidal B2-structured NiAl-rich phase and BCC-structured FeCr phases. As the number of the principal elements in the reinforcing phase decreases, the spinodal decomposition size gradually decreases. In the composites with varying ODS-CrFeNi reinforcement contents (5 %, 10 %, 15 %, 20 %), the occurrence of spinodal decomposition is also observed in the reinforcement. The spinodal decomposition size in the composite with 15 % and 20 % reinforcement content is smaller than that with 5 % and 10 % content. It is noteworthy that the incorporation of oxide-forming elements of Zr and Ti or only Zr together with Y₂O₃ in to the matrix result in different reinforcement structures. The former is typical spinodal decomposition, whereas latter displays a gradient network structure comprising a FCC-structured FeNi phase and a BCC-structured Cr-rich phase. The superior strength-ductility synergy, a compressive strength and strain of 7690 MPa and 15.5 %, which are 2.7 and 2 times higher than those of the unreinforced reference alloy, respectively, is achieved. This is mainly contributed by the novel gradient network structure in the reinforcement.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"921 ","pages":"Article 147590"},"PeriodicalIF":6.1,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142743723","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":"Optimizing mechanical and electrical properties of a nanostructured Cu-Ag alloy by aging at low temperatures","authors":"J.J. Li ,&nbsp;J.K. Zhang ,&nbsp;Y.Z. Tian","doi":"10.1016/j.msea.2024.147588","DOIUrl":"10.1016/j.msea.2024.147588","url":null,"abstract":"<div><div>Superior mechanical and electrical properties are desired in high-strength high-conductivity Cu alloys. It is challenging to achieve strength-ductility balance and strength-conductivity balance in Cu-Ag alloys. In this work, fully nanocrystalline Cu-2.9%Ag-0.6%Zr alloy was processed by cold rolling. Aging at different temperatures was conducted to modulate the microstructures and properties. Superior mechanical and electrical properties can be achieved by aging at low temperatures. Mechanisms for optimizing the strength, ductility and electrical conductivity were discussed.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"921 ","pages":"Article 147588"},"PeriodicalIF":6.1,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142722922","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":"Mechanical strengthening and corrosion behavior of friction stir welded dual-phase Fe50Mn30Co10Cr10 high entropy alloy","authors":"Shulei Sun ,&nbsp;Li Zhou ,&nbsp;Zhaoxu Yang ,&nbsp;Linghang Ma ,&nbsp;Xiaoguo Song","doi":"10.1016/j.msea.2024.147589","DOIUrl":"10.1016/j.msea.2024.147589","url":null,"abstract":"<div><div>This study explores the mechanical strengthening and corrosion behavior of friction stir welded joints in dual-phase Fe₅₀Mn₃₀Co₁₀Cr₁₀ high entropy alloy (HEA). The influence of microstructural evolution on the joint's mechanical properties was analyzed, along with an assessment of its corrosion resistance using electrochemical quantitative analysis. Additionally, the corrosion mechanisms of HEAs were explored by analyzing corrosion morphology. The results show that the nugget zone exhibits a low fraction of HCP phase, yet refined grains contribute to higher hardness compared to the base metal. The presence of multiple dislocations, HCP phases, and partially fine grains enhanced hardness in thermal-mechanical affected zone and heat affected zone, despite coarse grain does not favor hardness in these zones. Although fracture occurred in the heat affected zone due to inadequate inhibition of coarse grains on the crack propagation, the TRIP effect increased the joint's tensile strength to 97.1 % of the base metal. Reduced Mn segregation and grain refinement in the nugget zone promote the formation of thicker and more uniform passivation films, which exhibit superior corrosion resistance compared to the base metal. Conversely, a high fraction of HCP phase in the base metal elevated its tensile strength but reduced elongation by inducing high stress concentrations near phase boundaries. And the combined effects of component segregation, a high fraction of HCP phase, and bulk grain boundaries accelerate base material dissolution.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"921 ","pages":"Article 147589"},"PeriodicalIF":6.1,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142722925","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}