{"title":"Friction Stir Spot Welding of A6063S-T5 with Composite Coated Films","authors":"Murakoshi Terumichi, Takashima Yuki, Shibayanagi Toshiya","doi":"10.1080/09507116.2023.2275361","DOIUrl":"https://doi.org/10.1080/09507116.2023.2275361","url":null,"abstract":"Abstract A6063S-T5 is a material that is frequently used in construction materials, and in many cases, the surface of the material is coated with a composite coated films for durability and design purposes. However, if the composite coated films is interfered with as a foreign substance in the joint while the material is still coated, it may easily have an adverse effect on the joint strength. Therefore, it is usually necessary to remove the coated films before joining or to coat the part after joining. In this paper, the effect of composite coated films on the joining process of friction stir spot welding is clarified, and an efficient joining method for materials with composite coated films is proposed. It was shown that the effect of the composite coated films could be removed by using a triangular prism-shaped tool, and that the bonding area and strength could be controlled.","PeriodicalId":23605,"journal":{"name":"Welding International","volume":"166 ","pages":"67 - 78"},"PeriodicalIF":0.0,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136070080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Short time resistance spot welding of 1.2Gpa ultra-high strength steel using high frequency power supply","authors":"Yohsuke Abe, Nobuyori Yoshioka, Yoshihito Kinoshita, Satoshi Yamane","doi":"10.1080/09507116.2023.2275864","DOIUrl":"https://doi.org/10.1080/09507116.2023.2275864","url":null,"abstract":"AbstractThe task of 1.2 GPa ultra-high strength steel sheet in short time’s high current spot welding has been clarified. High current and short time spot welding system and high frequency power supply has been developed. In order to prevent spatter, new dual-pulse welding method in which primary energization, cooling and secondary energization has been proposed. By using this novel welding method, nugget diameter and tensile shear strength satisfied the target and spatter did not occur. New method of 1.2 GPa ultra-high strength steel sheet in short time and high current spot welding has been established.Keywords: Resistance spot weldingultra-high strength steelspattertensile shear strength Additional informationFundingThis research was commissioned by the New Energy and Industrial Technology Development Organization (NEDO) under the auspices of the Institute of Structural Materials for Advanced Materials (ISMA) of the New Energy and Industrial Technology Development Organization (NEDO).","PeriodicalId":23605,"journal":{"name":"Welding International","volume":"70 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136068538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ibrahim Sabry, Abdel-Hamid Ismail Mourad, Mohammad Alkhedher, Mohammad Reza Chalak Qazani, Ahmed El-Araby
{"title":"A Comparative Study of Multiple-Criteria Decision-Making Methods for selecting the best process parameters for friction stir welded Al 6061 alloy","authors":"Ibrahim Sabry, Abdel-Hamid Ismail Mourad, Mohammad Alkhedher, Mohammad Reza Chalak Qazani, Ahmed El-Araby","doi":"10.1080/09507116.2023.2270896","DOIUrl":"https://doi.org/10.1080/09507116.2023.2270896","url":null,"abstract":"AbstractThe selection of welding process parameters is a tedious operation that demands the process evaluation. Multi criteria decision-making strategies for assessing friction stir welding (FSW) process parameters are scanty. Therefore, a comparative study between five different multi-criteria decision-making methods was applied within friction stir welding process to show the deviations in the ranking of the alternatives. The goal is to find the welding parameters (including rotation speed, shoulder diameter, and travel speed) that result in the highest performance scores or rankings for the considered responses, such as ultimate tensile strength, hardness, and surface roughness. In the following, different decision-making strategies (including TOPSIS, GRA, hybrid GRA-TOPSIS, CoCoSo, and MACROS) are applied to calculate the weight of all different decision-making using entropy. The proposed methods in this study are validated by representing the accurate decision maker's preferences and consideration of uncertainty. The decision-makers choose GRA-TOPSIS and TOPSIS as the best approach with higher efficiency. GRA was determined to be more time-consuming and to have the most variety of outcomes, whereas CoCoSo and MACROS were unable to produce a definite best result. The study is highly promising for researchers and machining specialists to produce quality friction stir welds.Keywords: Decision-MakingTOPSISGRAMACROSCoCoSohybrid GRA-TOPSISDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.","PeriodicalId":23605,"journal":{"name":"Welding International","volume":"33 12","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136376404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The effect of friction stir welding on the microstructure and mechanical properties of the dissimilar SS304 and Al7075-T6 alloy joints","authors":"Ranjan Kumar, Manjaiah M, M J Davidson","doi":"10.1080/09507116.2023.2271391","DOIUrl":"https://doi.org/10.1080/09507116.2023.2271391","url":null,"abstract":"AbstractThis study focuses on the friction stir welding (FSW) of dissimilar materials, Al7075 alloy and SS304 stainless steel, in a butt configuration. The objective is to examine the impact of different operating conditions, including tool rotational speed, transverse speed, and tool offset, on the FSW process of the dissimilar sheets. Mechanical properties, specifically the ultimate tensile strength, were found to be influenced by rotational speed. Higher rotational speed resulted in decreased tensile strength due to increased heat generation in the weld zone, leading to the formation of a thicker intermetallic layer. Higher tool rotational speed and greater transverse feed rate improved weld joint performance. Microstructural changes and deformation properties were investigated using optical microscopy (OM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). The FSW process caused significant grain refinement, creating a fine and equiaxed recrystallized grain structure. Intermetallic compounds like Al13Fe14, Al3Fe2, and Al3Mg2 were identified in the interface zone. In summary, this study provides valuable insights into the FSW of dissimilar materials. It sheds light on mechanical properties, microstructural changes, and intermetallic compound formation in the welded joint, contributing to the understanding of FSW for dissimilar materials.Keywords: Friction stir weldingAl 7075SS304microstructureDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.","PeriodicalId":23605,"journal":{"name":"Welding International","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134972759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hemendra Kumar Srivastava, V. Balasubramanian, S. Malarvizhi, A. Gourav Rao
{"title":"Influence of post weld aging treatment on microstructural features and fatigue behaviour of unnotched and notched specimens of friction stir welded AA6061-T651 aluminium alloy joints under completely reversed stress cycle","authors":"Hemendra Kumar Srivastava, V. Balasubramanian, S. Malarvizhi, A. Gourav Rao","doi":"10.1080/09507116.2023.2267429","DOIUrl":"https://doi.org/10.1080/09507116.2023.2267429","url":null,"abstract":"AbstractA comparative investigation on rotating bending fatigue behaviour between unnotched and notched specimens of friction stir-welded (FSW) AA6061-T651aluminium alloy joints has been conducted under completely reversed cyclic loading (R = −1). Post-weld aging treatment was done for 8 h at 200°C on the welded joints. After post-weld aging treatment, the fatigue strength was significantly improved, while the grain size remained unchanged. Microstructural evolution before and after post-weld aging treatment was studied using orientation imaging microscopy (OIM) and transmission electron microscopy (TEM). It was found that post-weld aging treatment decreased dislocation density and facilitated precipitation hardening through the reprecipitation of fine β″(Mg2Si) particles. Fine particles of post-weld aged specimens of FSW joints were sheared by dislocations generated during cyclic loading, resulting in difficult crack initiation and tortuous crack propagation. Fractographic results confirmed that Post-weld aged specimens of FSW joints have better fatigue resistance than as-welded specimens, owing to the presence of significant precipitates along the grain boundary.Keywords: Friction stir weldingpost weld ageing treatmentfatigue behaviorS-N curvesmicrostructure AcknowledgementsThe authors wish to record sincere thanks to the Director of Naval Materials Research Laboratory (NMRL), DRDO, Ambernath Maharashtra for the financial support rendered through a CARS project No: NMRL/MMG/0401/04/NMRL253/CARS/145/2020-21. The authors thank the Naval Materials Research Laboratory (NMRL-DRDO), Mumbai, India, for providing base materials to carry out this investigation. The authors also thank IIT Kanpur for allowing them to use their EBSD facility.Disclosure statementThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.","PeriodicalId":23605,"journal":{"name":"Welding International","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136142657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Microstructural features and corrosion behavior of Inconel 625 components fabricated using Wire and Arc Additively Manufacturing (WAAM)","authors":"Karmuhilan M, Kumanan Somasundaram","doi":"10.1080/09507116.2023.2269087","DOIUrl":"https://doi.org/10.1080/09507116.2023.2269087","url":null,"abstract":"AbstractWire and Arc Additive Manufacturing (WAAM) is the predominant technique to process Nickel-based superalloys due to its low cost and high flexibility. This article discusses the microstructural features and corrosion resistance of two Inconel 625 parts manufactured using the WAAM technique. Using the WAAM process, two single-walled Inconel 625(IN625) components were produced additively for inter-pass layer temperatures(IPT) of 200 °C and 300 °C. The grain size changed with a change in IPTs, according to an investigation using electron backscatter diffraction (EBSD). The preferred grain orientation changed from the texture {001} < 001> to {001} < 101> as the IPT increased. Potentiodynamic polarization (PDP) was used to evaluate the corrosion behavior. The corrosion rate of the IPT 300 °C sample is 0.007255 mmpy, while the corrosion rate of the IPT 200 °C sample is 0.01315 mmpy. Tafel's extrapolation technique calculated the corrosion current density and corrosion current potential. The scanning electron microscope (SEM) explored the corroded area, and the Energy-dispersive X-Ray Spectroscope (EDS) examined the elemental composition.Keywords: MicrostructureCorrosionWire and Arc Additive ManufacturingInconel 625Inter pass layer temperatureDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.","PeriodicalId":23605,"journal":{"name":"Welding International","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136213898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bipin B Sharan, Prabha Chand, Mayuri Baruah, K Gopala Krishna
{"title":"OPTIMIZATION OF CMT WELDING PROCESS PARAMETERS OF DISSIMILAR HOT ROLLED E250 AND POLYMER SANDWICH STEEL LAP JOINTS","authors":"Bipin B Sharan, Prabha Chand, Mayuri Baruah, K Gopala Krishna","doi":"10.1080/09507116.2023.2265808","DOIUrl":"https://doi.org/10.1080/09507116.2023.2265808","url":null,"abstract":"AbstractLap joints of 1.5mm thin sheets of dissimilar hot rolled E250 with polymer sandwich steel (MPM) were produced by Cold metal transfer (CMT) process, closer to the real application. The polymer layer polystyrene-butadiene-styrene sandwiched between two DC06 sheets of MPM was found to be intact at significantly lower heat inputs (0.16-0.24 kJ/mm), which otherwise had been quite challenging during TIG welding leading to huge rejections. After several iterative trials for acceptable weld quality, experiments were conducted as per L9 orthogonal array,Taguchi technique with welding speed (WS),wire feed rate(WFR) and welding torch orientation (TO) as the process parameters.The joints were investigated through optical macrograph, micrographs, hardness, tensile lap shear tests and fractography on the fractured specimen. Optimum parameters were determined for maximizing shear strength. The sample with optimised parameters exhibited 6% improvement in shear strength achieving 152.09 MPa and polymer layer retention. ANOVA analysis suggested welding speed to be most significant parameter with 69.85% contribution affecting shear strength. Coefficient of determination (R2) for the shear strength was 87.26% derived from the linear regression model. Significantly lower error 0.96% computed from the confirmatory test concluded very effective optimization.HighlightsThin Sheets of polymer sandwich steel (MPM) sheets were joined successfully with E250 sheet without thermal disengagement of the polymer layer in MPM by CMT welding.Under optimal parameters MPM/E250 joints exhibited excellent mechanical properties.Fractography analysis revealed ductile failure mode.The error between experimental and predicted results by Taguchi was significantly lower and very well within the acceptable range.Key Words: Polymer sandwich SteelCMTTaguchi TechniqueANOVARegression AnalysisR2DisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.","PeriodicalId":23605,"journal":{"name":"Welding International","volume":"292 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135894894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Effect Of Variation Of The Electric Current On Physical and Mechanical Properties In A36 Steel Welding","authors":"None Suharno, Moh Rizal Fikri, Nugroho Agung Pambudi, Budi Harjanto, None Jumintono, Reza Rizkiana","doi":"10.1080/09507116.2023.2264175","DOIUrl":"https://doi.org/10.1080/09507116.2023.2264175","url":null,"abstract":"AbstractThe research objective was to determine the effect of current on microstructure, hardness values, and tensile strength of A36 steel before (raw material) and after welding using SMAW using electrodes E7016 diameter 3,2 mm. The research adopted an experimental method and utilized Olympus Metallurgical Microscope, Micro Vickers Hardness Tester, and Universal Testing Machine for data analysis. The results revealed that welding caused a change in the microstructure of the weld area into Grain boundary Ferrite (GF), Widmanstatten Ferrite (WF), and Acicular Ferrite (AF). The hardness test showed that higher current leads to greater hardness values. The specimens with a current of 130 Ampere had a hardness level of 181.39 VHN, which was higher than specimens with 120 Ampere (176.21 VHN) and 110 Ampere (159.56 VHN). The raw material had a hardness value of 125.4 VHN. The welding resulted in a difference in tensile stress, with specimens using 130 Ampere having the highest tensile strength level of 520.20 MPa, followed by 120 Ampere with 504.61 MPa, and 110 Ampere with 483.03 MPa. The research concludes that varying the electric current during welding affects the microstructure, tensile strength, and hardness value of Steel ASTM A36.Keywords: Shielded Metal Arc Welding (SMAW)ASTM A36 SteelMicrostructureTensile StrengthDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also. Acknowledgments:The authors would like to gratefully acknowledge Sebelas Maret University, Indonesia.Declaration of Interest:The authors declare there are no conflicts of interest.Author Contributions:The authors confirm contribution to the paper as follows: study conception and design: Suharno.; data collection: Moh Rizal Fikri, Nugroho Agung Pambudi, and Budi Harjanto; analysis and interpretation of results: Suharno and Jumintono; draft manuscript preparation: Reza Rizkiana. All authors have read and agreed to the published version of the manuscript.","PeriodicalId":23605,"journal":{"name":"Welding International","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135344801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Tribological analysis of cooling tank assisted hybrid friction stir welded 6061 aluminum alloy","authors":"Rajnish Singh, Yogesh Kumar","doi":"10.1080/09507116.2023.2258064","DOIUrl":"https://doi.org/10.1080/09507116.2023.2258064","url":null,"abstract":"Abstract:In the present work, the friction stir welding of aluminum alloy was done on the hybrid storage tank-assisted fixture at the Vertical Milling Centre. The three different storage media were used as air, water, and coolant. This study aimed to examine the effect of the cooling media in the hybrid fixture on the wear, coefficient of friction, hardness, and worn surface. The tool of mild steel was used for the welding process, and the wear of the tool was also examined for a better recommendation of tool material. In the FSW of the coolant-type welding process, it was found that the least wear was obtained at the different welding conditions. The higher rotational speed welded FSW joint increases the wear. The coefficient of friction exceeds the base material at 900 rpm in the FSW-W type joint. The average value of friction force at 500 rpm and 1000m sliding distance was 3N FSW air (FSW-A) and 5N base material. The average value of FF at 700 rpm and 1000m sliding distance was 1N FSW-A and 6 N for base material. The FF at 900 rpm was 5N FSW water type (FSW-W) and 1 N for FSW -A.Keywords: ICFSW-AICFSW-WICFSW-CwearDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.","PeriodicalId":23605,"journal":{"name":"Welding International","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134969193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Gaurav Nandan, K. S. Arora, Jaivindra Singh, Ajay Kumar
{"title":"Influence of process parameters on bead geometry and its effect on mechanical properties of CMT welding of automotive grade steel and aluminium alloy using aluminium based filler wire","authors":"Gaurav Nandan, K. S. Arora, Jaivindra Singh, Ajay Kumar","doi":"10.1080/09507116.2023.2256221","DOIUrl":"https://doi.org/10.1080/09507116.2023.2256221","url":null,"abstract":"Abstract This investigation aims to examine the effectiveness of torch position, welding-brazing parameters on the embedded bead profile and load carrying potential of the brazed joint of zinc coated DP600 steel and Al 5052 joined by cold metal transfer (CMT) technique. The base metals were joined at different torch position (−0.6, 0 and 0.6 mm) in lap joint position using Al-based filler wire. At different wire feed rate (WFR) 3, 4 and 5 m/min changes in bead shape and its geometry were observed. The various modes of failure were classified based on effective bonding length (LH–LV) and LH/θ ratio. The best combination of welding-brazing parameters at which the maximum load bearing capacity of 4.1 kN and enhanced bead properties was achieved at 0.6 mm torch position and WFR 5 m/min. The intermetallic compound layers formed during the process affect the tensile properties of weld-brazed joint. The possible intermetallics and the presence of major elements in intermetallic layer were analyzed by energy-dispersive X-ray spectroscopic analysis. Furthermore, in this investigation, it was also observed that the thickness of IMC layer increases with the increasing WFR and heat input up to a critical value of 10 µm.","PeriodicalId":23605,"journal":{"name":"Welding International","volume":"37 1","pages":"493 - 506"},"PeriodicalIF":0.0,"publicationDate":"2023-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48066037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}