Pub Date : 2023-12-19DOI: 10.24425/amm.2023.146205
{"title":"Mechanical Properties, Machinability and Corrosion Resistance of Zamak5 Alloyed by Copper","authors":"","doi":"10.24425/amm.2023.146205","DOIUrl":"https://doi.org/10.24425/amm.2023.146205","url":null,"abstract":"","PeriodicalId":8304,"journal":{"name":"Archives of Metallurgy and Materials","volume":"114 37","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138959138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-19DOI: 10.24425/amm.2023.146192
Y. Xing, P. Han, X. Wang
The 0.05 mm-thick 304 stainless steel foil was annealed within the temperature range from 950℃-1100℃ for 10 minutes to obtain different microstructures. and micro-deep drawing experiments of stainless steel foils with different tissue structures were conducted to obtain relevant material forming properties influenced by dimensional effects. On this basis, the influence of the microstructure characteristics on the forming performance of 304 stainless steel foil and the quality of the cup formed by using micro-drawing was studied, and its mechanism was discussed. it can be seen from the results that the stainless steel foil annealed at 950℃ exhibits poor forming performance, and the wrinkle phenomenon of the deep-drawn cup is obvious. At the annealing temperature of 1050℃, the quality of the deep drawing cup is significantly improved. When the annealing temperature reaches 1100℃, with the increase of the annealing temperature, the crystal grains size increase sharply, and the coarse-grain effect causes the uneven plastic deformation effect to be obvious. Besides, the drawing quality is obviously deteriorated. The observation of the microstructure of the deep drawing cup shows that the forming effect of the drawing cup is poor due to the rolling defects and the coarse grain effect. The 304 stainless steel drawing cup annealed at 1050℃ enjoys the best forming effect.
{"title":"Research on Formability of 304 Stainless Steel Foil Micro-Deep Drawing","authors":"Y. Xing, P. Han, X. Wang","doi":"10.24425/amm.2023.146192","DOIUrl":"https://doi.org/10.24425/amm.2023.146192","url":null,"abstract":"The 0.05 mm-thick 304 stainless steel foil was annealed within the temperature range from 950℃-1100℃ for 10 minutes to obtain different microstructures. and micro-deep drawing experiments of stainless steel foils with different tissue structures were conducted to obtain relevant material forming properties influenced by dimensional effects. On this basis, the influence of the microstructure characteristics on the forming performance of 304 stainless steel foil and the quality of the cup formed by using micro-drawing was studied, and its mechanism was discussed. it can be seen from the results that the stainless steel foil annealed at 950℃ exhibits poor forming performance, and the wrinkle phenomenon of the deep-drawn cup is obvious. At the annealing temperature of 1050℃, the quality of the deep drawing cup is significantly improved. When the annealing temperature reaches 1100℃, with the increase of the annealing temperature, the crystal grains size increase sharply, and the coarse-grain effect causes the uneven plastic deformation effect to be obvious. Besides, the drawing quality is obviously deteriorated. The observation of the microstructure of the deep drawing cup shows that the forming effect of the drawing cup is poor due to the rolling defects and the coarse grain effect. The 304 stainless steel drawing cup annealed at 1050℃ enjoys the best forming effect.","PeriodicalId":8304,"journal":{"name":"Archives of Metallurgy and Materials","volume":"119 11","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138959734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-19DOI: 10.24425/amm.2023.146206
P. Singh, R. K. Singh, A. K. Das
in the present study, the mechanical properties and high-temperature sliding wear behaviour of the Al6082-SiC-TiO 2 hybrid composite in different environmental conditions produced by the stir-casting process were investigated and distinguished with single-reinforced composites (Al6082-SiC and Al6082-TiO 2 ) and matrix alloy. The microstructure of composites exhibited a reasonably uniform scatter of particles in the aluminium matrix with good bonding between the matrix-particle interfaces. The hybrid composite’s hardness and ultimate tensile strength showed higher hardness and tensile strength than matrix alloy and single-reinforced composites, whereas trends were reversed for the elongation. The impact test of the materials was conducted at different temperatures (room temperature, 0°C, –25°C, –50°C, and –75°C). The hybrid composite shows higher impact strength than the other materials, and impact strength decreases with temperature because ductility decreases with temperature. The fracture surfaces were examined to identify the fracture mechanism. The sliding wear test was conducted at different temperatures (room temperature, 100°C, 175°C, 250°C and 325°C) to distinguish the tribological behaviour of materials. The weight loss of the materials was increased with an increase in temperatures. The hybrid composite shows a lower weight loss than the other condition samples, irrespective of the temperatures. The wear surfaces were examined to predict the material removal mechanism.
{"title":"Effect of Different Ceramic Reinforcements on Microstructure, Mechanical Properties and Tribological Behaviour of the Al6082 Alloy Produced by Stir Casting Process","authors":"P. Singh, R. K. Singh, A. K. Das","doi":"10.24425/amm.2023.146206","DOIUrl":"https://doi.org/10.24425/amm.2023.146206","url":null,"abstract":"in the present study, the mechanical properties and high-temperature sliding wear behaviour of the Al6082-SiC-TiO 2 hybrid composite in different environmental conditions produced by the stir-casting process were investigated and distinguished with single-reinforced composites (Al6082-SiC and Al6082-TiO 2 ) and matrix alloy. The microstructure of composites exhibited a reasonably uniform scatter of particles in the aluminium matrix with good bonding between the matrix-particle interfaces. The hybrid composite’s hardness and ultimate tensile strength showed higher hardness and tensile strength than matrix alloy and single-reinforced composites, whereas trends were reversed for the elongation. The impact test of the materials was conducted at different temperatures (room temperature, 0°C, –25°C, –50°C, and –75°C). The hybrid composite shows higher impact strength than the other materials, and impact strength decreases with temperature because ductility decreases with temperature. The fracture surfaces were examined to identify the fracture mechanism. The sliding wear test was conducted at different temperatures (room temperature, 100°C, 175°C, 250°C and 325°C) to distinguish the tribological behaviour of materials. The weight loss of the materials was increased with an increase in temperatures. The hybrid composite shows a lower weight loss than the other condition samples, irrespective of the temperatures. The wear surfaces were examined to predict the material removal mechanism.","PeriodicalId":8304,"journal":{"name":"Archives of Metallurgy and Materials","volume":" 847","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138960365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-19DOI: 10.24425/amm.2023.146200
K.A.A. HAlim, J. E. KEnnEdy, A. A. M. SAllEH, A. F. OSmAn, .F. OmAr, M. SunAr
.
.
{"title":"Micromechanical Modeling of Polyamide 11 Nanocomposites Properties using Composite Theories","authors":"K.A.A. HAlim, J. E. KEnnEdy, A. A. M. SAllEH, A. F. OSmAn, .F. OmAr, M. SunAr","doi":"10.24425/amm.2023.146200","DOIUrl":"https://doi.org/10.24425/amm.2023.146200","url":null,"abstract":".","PeriodicalId":8304,"journal":{"name":"Archives of Metallurgy and Materials","volume":" 48","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138960820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-19DOI: 10.24425/amm.2023.146190
Shih-Hsien Chang, Kun-Jie Liao, K. Huang, Cheng Liang
This study utilizes Ti-8nb-4Co alloys added to different proportions of Mo 2 C powders (1, 3, and 5 mass%) by the vacuum sintering process of powder metallurgy and simultaneously vacuum sinters the alloys at 1240, 1270, 1300, and 1330°C for 1 h, respectively. The experimental results indicate that when 3 mass% Mo 2 C powders were added to the Ti-8nb-4Co alloys, the specimens possessed the optimal mechanical properties after sintering at 1300°C for 1 h. The relative density was 98.02%, and the hardness and TRS were enhanced to 69.6 hRa and 1816.7 MPa, respectively. in addition, the microstructure of vacuum sintered Ti-8nb-4Co-3Mo 2 C alloys has both α and β-phase structures, as well as TiC precipitates. EBSD results confirm that the Mo 2 C in situ produced TiC during the sintering process and was uniformly dispersed in the grain boundary. Moreover, the reduced molybdenum atom acted as a β-phase stabilizing element and solid-solution in the titanium matrix.
本研究利用粉末冶金的真空烧结工艺，在 Ti-8nb-4Co 合金中加入不同比例的 Mo 2 C 粉末（1、3 和 5 质量%），同时分别在 1240、1270、1300 和 1330°C 下真空烧结合金 1 小时。实验结果表明，当在 Ti-8nb-4Co 合金中添加 3 质量%的 Mo 2 C 粉末时，试样在 1300°C 下烧结 1 小时后具有最佳的机械性能，相对密度为 98.此外，真空烧结 Ti-8nb-4Co-3Mo 2 C 合金的微观结构具有 α 和 β 相结构以及 TiC 沉淀。EBSD 结果证实，Mo 2 C 在烧结过程中原位生成了 TiC，并均匀地分散在晶界中。此外，还原钼原子在钛基体中起到了β相稳定元素和固溶体的作用。
{"title":"Effects of the Microstructure and Strengthening Mechanisms of Mo2C Powders Being Added to Ti-8Nb-4Co Alloy Via the Vacuum Sintering Process","authors":"Shih-Hsien Chang, Kun-Jie Liao, K. Huang, Cheng Liang","doi":"10.24425/amm.2023.146190","DOIUrl":"https://doi.org/10.24425/amm.2023.146190","url":null,"abstract":"This study utilizes Ti-8nb-4Co alloys added to different proportions of Mo 2 C powders (1, 3, and 5 mass%) by the vacuum sintering process of powder metallurgy and simultaneously vacuum sinters the alloys at 1240, 1270, 1300, and 1330°C for 1 h, respectively. The experimental results indicate that when 3 mass% Mo 2 C powders were added to the Ti-8nb-4Co alloys, the specimens possessed the optimal mechanical properties after sintering at 1300°C for 1 h. The relative density was 98.02%, and the hardness and TRS were enhanced to 69.6 hRa and 1816.7 MPa, respectively. in addition, the microstructure of vacuum sintered Ti-8nb-4Co-3Mo 2 C alloys has both α and β-phase structures, as well as TiC precipitates. EBSD results confirm that the Mo 2 C in situ produced TiC during the sintering process and was uniformly dispersed in the grain boundary. Moreover, the reduced molybdenum atom acted as a β-phase stabilizing element and solid-solution in the titanium matrix.","PeriodicalId":8304,"journal":{"name":"Archives of Metallurgy and Materials","volume":" 24","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138960906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-19DOI: 10.24425/amm.2023.146233
{"title":"Effect of History of Deformation and Heat Treatment on Cold Drawing Process Parameters and Final Properties of AISI 302 Stainless Steel Wire","authors":"","doi":"10.24425/amm.2023.146233","DOIUrl":"https://doi.org/10.24425/amm.2023.146233","url":null,"abstract":"","PeriodicalId":8304,"journal":{"name":"Archives of Metallurgy and Materials","volume":" 11","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138961012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-19DOI: 10.24425/amm.2023.146203
X. Zhang, S. Chen, Lu Li, P. Yang
arsenic is the only beneficial impurity for copper electrorefining through inhibiting anode passivation and the formation of floating slimes. The behaviour of copper anodes with different content of arsenic were studied at high current density (>280 a/m 2 ). it showed that low arsenic anodes (as < 300 ppm) easily generated anode passivation, floating slimes and cathode nodules during the electrorefining proccess. The floating slimes, electrolyte, cathode and anode were observed and analyzed. as result, low arsenic anodes were more likely to be passivated due to their microstructure defects and irregular microstructure. increasing electrolyte temperature and addition of glycerol were propitious to reduce low arsenic anodes’ passivation. The floating slimes occured when the concentration of as(iii) in electrolyte decreased to 1 g/L, and they would be precipitated by polyacrylamide. all measures greatly improved the cathode quality at current density of 300 a/m 2 .
{"title":"The Behaviour of Low Arsenic Copper Anodes at High Current Density in Electrorefining","authors":"X. Zhang, S. Chen, Lu Li, P. Yang","doi":"10.24425/amm.2023.146203","DOIUrl":"https://doi.org/10.24425/amm.2023.146203","url":null,"abstract":"arsenic is the only beneficial impurity for copper electrorefining through inhibiting anode passivation and the formation of floating slimes. The behaviour of copper anodes with different content of arsenic were studied at high current density (>280 a/m 2 ). it showed that low arsenic anodes (as < 300 ppm) easily generated anode passivation, floating slimes and cathode nodules during the electrorefining proccess. The floating slimes, electrolyte, cathode and anode were observed and analyzed. as result, low arsenic anodes were more likely to be passivated due to their microstructure defects and irregular microstructure. increasing electrolyte temperature and addition of glycerol were propitious to reduce low arsenic anodes’ passivation. The floating slimes occured when the concentration of as(iii) in electrolyte decreased to 1 g/L, and they would be precipitated by polyacrylamide. all measures greatly improved the cathode quality at current density of 300 a/m 2 .","PeriodicalId":8304,"journal":{"name":"Archives of Metallurgy and Materials","volume":" 41","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138961452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-19DOI: 10.24425/amm.2023.146229
F. S. Shaharudin, F. F. Zainal, F. hayaZi, Parimin, i.m. nadZri, S. haStuty, KuSbiantoro
this research was conducted to examine the corrosion behaviour of mild steel bar embedded in geopolymer paste based fly ash Class F during curing and non-curing process. the geopolymer paste was fabricated by blending in the fly ash with alkaline activators (naoh solution with molarity of 12 m, 2.5 ratio of solution na2Sio3/naoh). the paste was produced in 50 mm × 50 mm × 50 mm mould where the mild steel bar of 100 mm (length) × 12 mm (diameter) was embedded at the center of geopolymer paste. this is to comprehend the corrosion behaviour of mild steel embedded in geopolymer paste with and without curing process. Process of curing is carried out for 24 hours at a temperature of 60°C in oven. While on the contrary, the non-curing process will only be leave at room temperature. both samples were tested after 28 days of curing to determine the corrosion behaviour, phase analysis and morphology analysis. in accordance with the morphology analysis, it shows that the fly ash was totally reacted with alkaline solutions in curing geopolymer paste sample while the non-curing geopolymer paste has shown the unreacted fly ash with high number of pores. the phase analysis of mild steel embedded in this geopolymer paste during curing and without curing process has proven that the presence of new crystallographic peak which also known as passive layer occurred. the potential values result by oCP testing shows the curing sample has highest potential values as compared to the non-curing sample ones.
{"title":"Investigation of Corrosion Behaviour of Mild Steel Embedded in Geopolymer Paste with Curing and Non-Curing Process","authors":"F. S. Shaharudin, F. F. Zainal, F. hayaZi, Parimin, i.m. nadZri, S. haStuty, KuSbiantoro","doi":"10.24425/amm.2023.146229","DOIUrl":"https://doi.org/10.24425/amm.2023.146229","url":null,"abstract":"this research was conducted to examine the corrosion behaviour of mild steel bar embedded in geopolymer paste based fly ash Class F during curing and non-curing process. the geopolymer paste was fabricated by blending in the fly ash with alkaline activators (naoh solution with molarity of 12 m, 2.5 ratio of solution na2Sio3/naoh). the paste was produced in 50 mm × 50 mm × 50 mm mould where the mild steel bar of 100 mm (length) × 12 mm (diameter) was embedded at the center of geopolymer paste. this is to comprehend the corrosion behaviour of mild steel embedded in geopolymer paste with and without curing process. Process of curing is carried out for 24 hours at a temperature of 60°C in oven. While on the contrary, the non-curing process will only be leave at room temperature. both samples were tested after 28 days of curing to determine the corrosion behaviour, phase analysis and morphology analysis. in accordance with the morphology analysis, it shows that the fly ash was totally reacted with alkaline solutions in curing geopolymer paste sample while the non-curing geopolymer paste has shown the unreacted fly ash with high number of pores. the phase analysis of mild steel embedded in this geopolymer paste during curing and without curing process has proven that the presence of new crystallographic peak which also known as passive layer occurred. the potential values result by oCP testing shows the curing sample has highest potential values as compared to the non-curing sample ones.","PeriodicalId":8304,"journal":{"name":"Archives of Metallurgy and Materials","volume":" 16","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138962090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-19DOI: 10.24425/amm.2023.146193
{"title":"Material Aspects of Historic Fine Ceramics","authors":"","doi":"10.24425/amm.2023.146193","DOIUrl":"https://doi.org/10.24425/amm.2023.146193","url":null,"abstract":"","PeriodicalId":8304,"journal":{"name":"Archives of Metallurgy and Materials","volume":" 1046","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138960333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-19DOI: 10.24425/amm.2023.146202
P. Kaliuzhnyi, ShalevSKa, SliuSarev
The article considers the method of obtaining reinforced castings from gray cast iron by lost foam casting. The aim of this study was to determine the microstructure formation of gray cast iron reinforced with inserts of carbon and stainless steel in this casting method. The results of the research have shown that the products of destruction of expanded polystyrene have a positive effect on the bonding formation of cast iron with reinforcing inserts. When steel wire is used as reinforcement, a decarbonized layer of cast iron is being formed around it, in which the inclusions of graphite are smaller and their quantity is less than in the main metal. Due to carburization, the surface structure of the reinforcement changes from ferrite to pearlite with cementite. Steel wire reinforcement can be effective in increasing strength and toughness of gray cast iron. The usage of stainless steel reinforcement leads to the formation of a transition layer on the part of the matrix metal. it contains ledeburite with dissolved chromium, which increase the wear resistance of cast iron.
{"title":"Microstructure of Reinforced Cast Iron Produced by Lost Foam Casting","authors":"P. Kaliuzhnyi, ShalevSKa, SliuSarev","doi":"10.24425/amm.2023.146202","DOIUrl":"https://doi.org/10.24425/amm.2023.146202","url":null,"abstract":"The article considers the method of obtaining reinforced castings from gray cast iron by lost foam casting. The aim of this study was to determine the microstructure formation of gray cast iron reinforced with inserts of carbon and stainless steel in this casting method. The results of the research have shown that the products of destruction of expanded polystyrene have a positive effect on the bonding formation of cast iron with reinforcing inserts. When steel wire is used as reinforcement, a decarbonized layer of cast iron is being formed around it, in which the inclusions of graphite are smaller and their quantity is less than in the main metal. Due to carburization, the surface structure of the reinforcement changes from ferrite to pearlite with cementite. Steel wire reinforcement can be effective in increasing strength and toughness of gray cast iron. The usage of stainless steel reinforcement leads to the formation of a transition layer on the part of the matrix metal. it contains ledeburite with dissolved chromium, which increase the wear resistance of cast iron.","PeriodicalId":8304,"journal":{"name":"Archives of Metallurgy and Materials","volume":" 83","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138961254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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