Journal of Advanced Joining Processes最新文献

{"title":"Investigations to improve the tool life during thermomechanical and incremental forming of steel auxiliary joining elements","authors":"T Borgert,&nbsp;AB Nordieker,&nbsp;E Wiens,&nbsp;W Homberg","doi":"10.1016/j.jajp.2024.100185","DOIUrl":"https://doi.org/10.1016/j.jajp.2024.100185","url":null,"abstract":"<div><p>Modern vehicles as well as structures consist more and more often of a multi material mix. In addition to the use of light materials (e. g. aluminium) to optimise lightweight construction potential, higher strength alloys are being used more and more frequently. With the different material combinations, the requirements for the joining technology also increase. Thus (due to restrictions in the area of thermal joining processes) the joining of different material combinations is often realised by mechanical joining technology. Even though different joining tasks (dissimilar material or sheet thicknesses) can be solved by mechanical joining technology in general, it is often required to switch between appropriate auxiliary joining elements and even joining technique. To adapt the auxiliary elements to the individual requirements of each joint an innovative manufacturing process of customisable auxiliary joining elements has been developed. The use of the incremental, thermomechanical manufacturing process called friction-spinning for the manufacturing of adaptive auxiliary joining elements enables to individualise each element for the subsequent joining process. However, this advantage comes at the cost of a high mechanical and thermal loads on the forming tools. These loads also depend on the process design (trajectory, feed, rotational speed) and have to be controlled in order to improve the tool life. For a more profound process knowledge and to better understand the corellation of the individual process variables, a series of tests with varying process parameters were carried out in a partial factorial design of experiments. The results show not only an possible improvement in the tool life, but also the required process design for a higher reproducibility of the auxiliary joining element geometry and the possibility of positively influencing the geometry to achieve a force-closure of the joint.</p></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"9 ","pages":"Article 100185"},"PeriodicalIF":4.1,"publicationDate":"2024-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666330924000025/pdfft?md5=5e04eb0f96de34eb5997f7604d02d3c9&pid=1-s2.0-S2666330924000025-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139433406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel joining technology for metal and polymer sheets","authors":"MM Kasaei ,&nbsp;RJC Carbas ,&nbsp;EAS Marques ,&nbsp;LFM da Silva","doi":"10.1016/j.jajp.2024.100184","DOIUrl":"10.1016/j.jajp.2024.100184","url":null,"abstract":"<div><p>This paper introduces a novel joining process for producing hybrid metal-polymer joints. The process, called hole hemming, involves deforming the metal sheet to establish a mechanical interlock with the polymer sheet, requiring neither heating nor auxiliary elements. The applicability of this process is tested for joining aluminum and polycarbonate (PC) sheets. Initially, an analytical design method is presented to achieve a connection without failure and with a mechanical interlock. Subsequently, the accuracy of the predictions is assessed through experiments and finite element simulations, employing the modified Mohr-Coulomb criterion for the prediction of ductile damage. Additionally, a new design for hole-hemmed joints, involving the incorporation of branches in the hole of the outer sheet, is introduced to expand the process window of this novel joining technology. Finally, the mechanical behavior of four different types of hybrid hole-hemmed joints (HHH joints) are evaluated through single-lap shear tests. The results show that the hole hemming process can successfully join AA6082-T4 and PC sheets, validating the proposed designs and ideas. The new hybrid joints demonstrate a maximum force and displacement of 1.6 kN and 12.9 mm, respectively, in the shear test, indicating significant potential of the proposed technology for joining metal and polymer sheets.</p></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"9 ","pages":"Article 100184"},"PeriodicalIF":4.1,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666330924000013/pdfft?md5=2ae40f26653a888df822a286384f3aa7&pid=1-s2.0-S2666330924000013-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139393714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of the influence of pulse parameters on the resulting weld seam quality in pulsed electron beam welding of AW 6061","authors":"M. Troise,&nbsp;T. Krichel,&nbsp;S. Olschok,&nbsp;U. Reisgen","doi":"10.1016/j.jajp.2023.100183","DOIUrl":"https://doi.org/10.1016/j.jajp.2023.100183","url":null,"abstract":"<div><p>Utilizing pulsed lasers in favor of a continuous wave in laser beam welding is a well-established method to achieve higher process efficiency and reduce heat input into the workpiece, which is especially useful for thin-walled workpieces (Steen, 2005). In addition, pulsed processes have shown to lead to smaller grain sizes due to higher cooling rates, which can lead to a reduction in hot cracks in some aluminum alloys (Beiranvand et al., 2019). Since an electron beam can also be pulsed, a technique industrially utilized in electron beam drilling, the same principles apply (Schultz, 2000). However, pulsed electron beam welding is rarely used in industrial welding applications due to the risk of pores, spiking and sputtering resulting from the pulsed process dynamic, especially in the deep welding regime (Kautz, 1991). This study aims to develop a pulsed electron beam welding process for AW 6061 sheet metal, which is susceptible to hot cracking. The influence of the welding and pulse parameters, as well as the combination of a pulsed beam with high frequency beam oscillation is discussed. Furthermore, suitable welding parameters for pulsed electron beam welding of AW 6061 are developed, and the increased efficiency of pulsed welding is shown by comparison to continuous welds.</p></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"9 ","pages":"Article 100183"},"PeriodicalIF":4.1,"publicationDate":"2023-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666330923000456/pdfft?md5=a22c4bb526a1baafdf994c889d73e8c4&pid=1-s2.0-S2666330923000456-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139107648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In situ localised post-weld heat treatment with electron beam welding of S690QL steel","authors":"Raghawendra Sisodia ,&nbsp;Marek Weglowski ,&nbsp;Piotr Sliwinski","doi":"10.1016/j.jajp.2023.100182","DOIUrl":"https://doi.org/10.1016/j.jajp.2023.100182","url":null,"abstract":"<div><p>The objective of this research is to assess the influence of in-situ localised electron beam post-weld heat treatment (LEB-PWHT) on the microstructure and mechanical properties of high-strength S690QL steel welded joints utilising highly sophisticated electron beam welding (EBW) technology. Although EBW is well-known for creating high-quality welds, the addition of the novel LEB-PWHT technique may significantly improve the characteristics of the welded joints. To systematically analyse the impacts of PWHT on the welded joints, the study employs microstructural analysis like optical microscopy and mechanical properties like microhardness testing, bending, tensile, and impact tests. Furthermore, tensile fractography analysed by scanning electron microscopy (SEM) to provide detailed insights into the fracture behaviour of the welded joints. The results show that the in-situ PWHT approach improves the microstructure and mechanical characteristics of the welded joints, such as a lower hardness peak in the heat affected zone (HAZ), increased tensile strength (5%), and improved toughness by 7 times. LEB-PWHT fractured surface revealed smaller, more sharply defined dimples and micro-voids. These results suggest that in-situ PWHT is an attractive option for improving the quality and performance of welds in a wide range of applications incorporating S690QL steel.</p></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"9 ","pages":"Article 100182"},"PeriodicalIF":4.1,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666330923000444/pdfft?md5=cd0b6577fdb63741c5f48c82dd12f702&pid=1-s2.0-S2666330923000444-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139109264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electropolymerization of acrylic acid on steel for enhanced joining by plastic deformation","authors":"B. Duderija ,&nbsp;F. Sahin ,&nbsp;D. Meinderink ,&nbsp;J.C. Calderón-Gómez ,&nbsp;H.C. Schmidt ,&nbsp;W. Homberg ,&nbsp;G. Grundmeier ,&nbsp;A. González-Orive","doi":"10.1016/j.jajp.2023.100181","DOIUrl":"https://doi.org/10.1016/j.jajp.2023.100181","url":null,"abstract":"<div><p>Resource-efficient electrochemical polymerization of acrylic acid (AA) on steel (DC04), from mildly acid Zn²⁺/ AA-containing aqueous solutions, is presented as an effective and sustainable thin film technology which allows for a precise control of the polymer thickness and morphology. The steel substrates were potentiostatically polarized to -1.4 V (vs. Ag/AgCl) or cycled between +0.1 to -1.4 V (vs. Ag/AgCl) in a degassed 2.0 M AA and 0.2 M ZnCl₂-containing aqueous electrolyte solution at pH 6. FE-SEM, AFM, FT-IRRAS, XPS, and electrochemical measurements shed light on the structural and chemical features exhibited by the as-prepared polyacrylic acid (PAA) thin films. When PAA-modified DC04 plates are joined to Al EN AW-1050A H24 specimens by plastic deformation using cold pressure welding (CPW), tensile strength testing unveiled the macroscopic interfacial adhesion-promoting capabilities exhibited by PAA layers to the opposing aluminum oxide surfaces. Carboxylate moieties present in the PAA are shown to form stable chemical bonds with metal oxide surfaces and with amine-epoxy-based resins. Interestingly, higher maximum shear force values are obtained for the PAA films when Zn metallic deposits are not present in the organic layer, but, when these welded specimens are heated up to 200 °C in a N₂ atmosphere, it occurred exactly the opposite: Zn particle-containing PAA films showed the highest maximum shear force values for the same deposition time.</p></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"9 ","pages":"Article 100181"},"PeriodicalIF":4.1,"publicationDate":"2023-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666330923000432/pdfft?md5=25fa3260d6baf8151d08076dc2b62956&pid=1-s2.0-S2666330923000432-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139107647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Feasibility of friction stir welding using a hemispherical tool tilted towards the retreating side","authors":"D. Ambrosio,&nbsp;A. Sharma,&nbsp;M. Mukuda,&nbsp;Y. Morisada,&nbsp;H. Fujii","doi":"10.1016/j.jajp.2023.100180","DOIUrl":"10.1016/j.jajp.2023.100180","url":null,"abstract":"<div><p>The use of a hemispherical tool tilted towards the retreating side for friction stir welding 6061-T6 aluminum alloy is investigated. Joints with smooth surfaces and without internal voids are obtained. Under the same welding and rotational speeds, adapting the tilt angle makes it possible to weld various thicknesses up to 3.5 mm. Plunge depth and tilt angle are demonstrated to be key geometrical parameters driving material flow when using the hemispherical tool. Microstructural features in the weld are equiaxed and refined grains below 5 µm in the stirred zone and narrow thermo-mechanical affected zones. The through-thickness thermomechanical gradient developing beneath the hemispherical tool leads to different extents of dynamic recrystallization and recovery in the stirred zone. The tool orientation towards the retreating side and the division of the tool-workpiece interaction in continuous and intermittent contact leads to an asymmetrical thermal field around the stirred zone. Hence, the new derivative friction stir welding solution allows the welding of multiple aluminum alloy blank thicknesses using the same tool.</p></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"9 ","pages":"Article 100180"},"PeriodicalIF":4.1,"publicationDate":"2023-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666330923000420/pdfft?md5=0378ecf6ad011967a39435fc58bd66eb&pid=1-s2.0-S2666330923000420-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138993200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cold spot joining of high-strength steel sheets","authors":"Takumi Aibara ,&nbsp;Masayoshi Kamai ,&nbsp;Yoshiaki Morisada ,&nbsp;Kohsaku Ushioda ,&nbsp;Takaaki Miyauchi ,&nbsp;Shinichi Hasegawa ,&nbsp;Hidetoshi Fujii","doi":"10.1016/j.jajp.2023.100179","DOIUrl":"10.1016/j.jajp.2023.100179","url":null,"abstract":"<div><p>A novel solid-state joining method, called cold spot joining (CSJ), has been successfully developed. In this method, the material near the joining interface undergoes plastic deformation under high pressure, forming a joining interface, while oxide layers at the interface are fragmented and expelled to the exterior. High-strength steel sheets (HSS) with strengths of 780 MPa were joined under various conditions. The joining temperature can be adjusted by applying pressure during CSJ. Applying suitable pressure results in solid-state joining, and microstructural observations, alongside fracture morphology, indicate that the formation of a brittle structure was effectively prevented. Furthermore, cross-tensile strength measurements were conducted on steel sheets of varying strength grades, ranging from 270 to 1180 MPa and exhibited that the cross-tensile strength increased with increasing tensile strength.</p></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"9 ","pages":"Article 100179"},"PeriodicalIF":4.1,"publicationDate":"2023-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666330923000419/pdfft?md5=b30f6e00b9a336d1cff19505afa381f1&pid=1-s2.0-S2666330923000419-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139019736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermographic procedure for the assessment of Resistance Projection Welds (RPW): Investigating parameters and mechanical performances","authors":"G. Dell'Avvocato,&nbsp;D. Palumbo","doi":"10.1016/j.jajp.2023.100177","DOIUrl":"https://doi.org/10.1016/j.jajp.2023.100177","url":null,"abstract":"<div><p>This study presents a non-destructive testing (NDT) thermographic procedure for assessing the quality and mechanical strength of Resistance Projection Welded (RPW) joints with rectangular embossments. We analysed twelve RPW joints by systematically varying process parameters based on a factorial design. These joints underwent flash thermography followed by mechanical tests to evaluate the maximum breaking force (F_max). Significant statistical correlations between process parameters (time and force) and F_max were established. Furthermore, we found a correlation (p-value 0.86) between the optically measured fused region and F_max. Subsequently, we developed a pulsed phase thermography-based procedure for non-destructively measuring the fused region, resulting in an average difference of approximately 4 % compared to optical measurements. An empirical linear relationship was derived to correlate the welded area obtained by thermal data with F_max, enabling the estimation of mechanical joint strength through non-destructive pulsed thermography. This research offers a promising approach for assessing the mechanical integrity of RPW joints using thermal imaging techniques.</p></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"9 ","pages":"Article 100177"},"PeriodicalIF":4.1,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666330923000390/pdfft?md5=2e90d2f9010db3931cdd1d353f17e90d&pid=1-s2.0-S2666330923000390-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138739213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of vacuum brazing time on the microstructure and mechanical properties of Ti-6Al-4 V to 316 L dissimilar joint using BNi-2 filler metal","authors":"Milad Foumani,&nbsp;Homam Naffakh-Moosavy","doi":"10.1016/j.jajp.2023.100176","DOIUrl":"https://doi.org/10.1016/j.jajp.2023.100176","url":null,"abstract":"<div><p>Due to the distinct differences in physical and metallurgical properties, it is hard to join titanium alloys to stainless steels directly via conventional welding processes. In this research, the grade 5 titanium alloy was subjected to brazing with austenitic stainless steel through the vacuum furnace, and the process was conducted above the <em>β</em> transition temperature (BTT). In order to reduce brittle intermetallic formation, a nickel base filler metal (Ni-6.6Cr-4.5Si-3B) was employed under a vacuum condition, and the effect of time on the microstructure and mechanical properties of the joints was investigated. The brazing temperature led to the thickening of the interface to 400 <em>µ</em>m, toward the titanium alloy, and the FeTi formed adjacent to the diffusion affected zone (DAZ). Moreover, the isothermal solidified zone (ISZ) widened during the whole process, which, led to higher dissolution of the titanium base metal in the ISZ. Because of the widening of the interfaces, there were no Ni-rich compounds or residual filler metal in this region. SEM result showed that TiB strengthening borides, which were distributed after 45 min, and this evolution caused an increase in the shear strength of the joint up to 67 MPa. Fractography analyses and XRD results of the fractured surfaces revealed that the Ti₂Ni phase, which formed in the athermaly solidified zone (ASZ) during a two-step solidification reaction, caused the brittle fracture in all joints.</p></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"9 ","pages":"Article 100176"},"PeriodicalIF":4.1,"publicationDate":"2023-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666330923000389/pdfft?md5=0e438577d44be7eb650893bc666ab801&pid=1-s2.0-S2666330923000389-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138739212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A comprehensive review of the S-N fatigue behaviour of adhesive joints","authors":"F.Castro Sousa ,&nbsp;P. Zamani ,&nbsp;A. Akhavan-Safar ,&nbsp;L.F.M. da Silva","doi":"10.1016/j.jajp.2023.100178","DOIUrl":"https://doi.org/10.1016/j.jajp.2023.100178","url":null,"abstract":"<div><p>The complex fatigue failure mechanisms render it challenging to arrive at definitive conclusions regarding the behaviour of adhesive joints under cyclic loading. The goal of this review paper is to compile the various research conducted in this field and offer insights into the S-N fatigue response of adhesive joints. This review delves into experimental studies that investigate different factors influencing the fatigue life of bonded structures, encompassing joint geometry, environmental conditions, and loading conditions. Subsequently, the various approaches to improve the fatigue performance and durability of bonded joints are explored. It also examines S-N based life prediction methods, analysing their merits and limitations in assessing the fatigue life of adhesive joints under different conditions. In addition, this review pays attention to studies that focus on real bonded joints. It highlights the importance of bridging the gap between simplified conditions and real-world performance to ensure the durability and safety of bonded joints under service conditions.</p><p>The review demonstrates that factors such as adhesive/adherend thickness, fillet, and overlap shape (e.g., wavy pattern, step, scarf) do impact fatigue life. However, the critical role played by overlap length in the fatigue life of bonded joints stands out. Improving fatigue life through adjustments, such as adhesive/adherend thickness, depends on the specific case. Therefore, further investigations are warranted in this area. The review suggests that carbon nanoparticles can enhance bonded joint fatigue strength. Hybrid reinforcement with carbon and organic nanoparticles, like silica, offers a cost-effective path to improve joint life. Regarding life prediction, there is currently no universal fatigue model that considers all parameters impacting the fatigue life of adhesive joints. Fatigue analysis methods considered for real adhesive joints vary between sectors. Initial designs frequently employ indirect fatigue life assessment methods, yet direct fatigue analysis through testing actual joints remains essential for ensuring reliability.</p></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"9 ","pages":"Article 100178"},"PeriodicalIF":4.1,"publicationDate":"2023-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666330923000407/pdfft?md5=27e90e4fe50e1ec7f6769f83da05d421&pid=1-s2.0-S2666330923000407-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138656116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}