Journal of Manufacturing Processes最新文献

{"title":"Investigation of thermal behavior and mechanical properties in hot stamping of aluminized 30MnB5 with an integrated process window design","authors":"Jea-Myoung Park,&nbsp;Kye-Jeong Park,&nbsp;Je-Youl Kong,&nbsp;Seung-Chae Yoon","doi":"10.1016/j.jmapro.2025.06.105","DOIUrl":"10.1016/j.jmapro.2025.06.105","url":null,"abstract":"<div><div>Hot stamping technology has emerged as an essential process for manufacturing lightweight and ultra-high-strength automotive components, particularly with the increasing adoption of electric vehicles. Among advanced materials, aluminized 30MnB5 steel, with tensile strengths exceeding 1.8 GPa, provides a compelling combination of crash safety enhancement and weight reduction. However, its mechanical properties are highly sensitive to processing conditions, necessitating systematic optimization. This study introduces an integrated Process Window (PW) that incorporates heating, transfer, and cooling stages to ensure efficient and reliable manufacturing. Experimental results identified 870 °C as the optimal heating temperature for 30MnB5 steel. At this temperature, the steel achieved a tensile strength exceeding 1.8 GPa, a yield strength of approximately 1.2 GPa, and an elongation of 6.8 %. Additionally, the interdiffusion layer thickness in the Al-Si coating was reduced to approximately 3.8 μm, the prior austenite grain size was refined to 9.6 μm, and hydrogen absorption was suppressed by about 45 % compared to higher heating temperatures. These conditions collectively enhance weldability and ensure consistent mechanical performance. The sheet thickness was shown to significantly influence thermal behavior, impacting heating times, ambient exposure, and die-cooling. The derived temperature-time relationship functions enable tailored process adjustments to achieve consistent strength and formability across varying sheet thicknesses. Unlike conventional PW, which primarily addresses heating conditions, the proposed integrated PW encompasses the entire hot stamping process. It aims to reduce inefficiencies and improve process stability. By quantitatively linking process parameters to microstructural evolution and mechanical properties, this study establishes a robust framework for the production of lightweight, ultra-high-strength automotive components. The findings also contribute to advancing sustainable manufacturing practices by optimizing energy consumption and process efficiency.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"150 ","pages":"Pages 1216-1227"},"PeriodicalIF":6.1,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144596954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Resistance welding of thermoplastic composites using novel heating element of graphite film","authors":"Jixiao Han ,&nbsp;Hongchuan Zhang ,&nbsp;Yifan Liu ,&nbsp;Jianhui Su ,&nbsp;Xueyan Zhang ,&nbsp;Caiwang Tan ,&nbsp;Huatao Wang ,&nbsp;Xiaoguo Song","doi":"10.1016/j.jmapro.2025.07.026","DOIUrl":"10.1016/j.jmapro.2025.07.026","url":null,"abstract":"<div><div>The application of thermoplastic composites has advanced structural lightweight, necessitating effective methods for achieving stable joints. In this study, a laser-ablated graphite film was developed as a novel heating element, introducing an innovative approach to the resistance welding of carbon fiber-reinforced polyamide 66 (CF/PA66) thermoplastic composites. Systematic experiments and analyses verified the performance of the graphite heating element in providing uniform heat and efficient welding during the process. Through systematic experiments and analysis, the graphite heating element demonstrated uniform heat generation and high welding efficiency. The use of this heating element enhanced resin flow and improved the temperature distribution uniformity at the welding interface. Moreover, it eliminated the need for dissimilar metallic materials, thereby reducing stress concentrations and minimizing edge effects during the welding process. This novel heating element shows great potential for resistance welding of thermoplastic composites, offering a groundbreaking solution for joining high-performance and lightweight structures.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"151 ","pages":"Pages 41-53"},"PeriodicalIF":6.1,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144604678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ultrafast laser processing of shaped film cooling holes for aero-turbine blades: Surface integrity, parameter influence and forming mechanism","authors":"Meng Li ,&nbsp;Zhixun Wen ,&nbsp;Ping Wang ,&nbsp;Yuxing Liu ,&nbsp;Zhufeng Yue","doi":"10.1016/j.jmapro.2025.07.017","DOIUrl":"10.1016/j.jmapro.2025.07.017","url":null,"abstract":"<div><div>Shaped film cooling holes (FCHs) can effectively improve the film cooling efficiency of turbine blades, but due to their complex structure and precision requirements, there is currently no reliable and high-quality machining method. In this paper, a segmented processing method of fan-shaped FCHs is proposed, which realizes high-quality processing of fan-shaped FCHs. The effects of processing parameters on the machining efficiency, geometric accuracy and surface morphology of fan-shaped FCHs were analyzed. And the microstructure, composition, surface roughness and residual stress of the hole wall under specific processing parameters were characterized. The influence mechanism of processing parameters on the processed results is clarified by laser overlap rate and laser energy density of the processing area. The important role of focus compensation in the segmented machining method is discussed. The formation mechanism of microstructures was explained by the plasma exciton theory and the energy shielding effect. Furthermore, the process method is promoted through expansion section model segmentation and processing attitude adjustment to realize the processing of cat-ear-shaped and bat-face-shaped FCHs.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"150 ","pages":"Pages 1194-1215"},"PeriodicalIF":6.1,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144596952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Managing thermal states in multi-material additive manufacturing of polymer-ceramic structures","authors":"Olorunfemi J. Esan ,&nbsp;Christopher J. Hansen ,&nbsp;Alireza Amirkhizi ,&nbsp;Ian M. McAninch ,&nbsp;Stephen R. Cluff ,&nbsp;Pauline M. Smith ,&nbsp;Amy M. Peterson","doi":"10.1016/j.jmapro.2025.06.102","DOIUrl":"10.1016/j.jmapro.2025.06.102","url":null,"abstract":"<div><div>Multi-material additive manufacturing (MMAM) enables the fabrication of components with a wide range of properties and functionalities. However, integrating materials such as ceramics, known for their high strength, chemical and wear resistance, with polymers, exhibiting toughness and ductility, remains challenging due to their vastly different processing temperatures. In this work, we modeled the dissimilar thermal processing of polymers and ceramics in a single AM platform. Ceramic processing was simulated using powder bed fusion (PBF), while polymer processing can be achieved using material extrusion, vat photopolymerization, material jetting, and PBF for powder-based polymers. Physical gaps between polymer and ceramic were designed to reduce heat transfer to the polymer during ceramic sintering. A range of common thermoplastic and thermosets polymers were studied. Results showed that increased laser power and scan speed raised actual processing temperatures. Thermoplastic polymers exhibited a narrow processing window, melting with increased laser power and scan speed, particularly at smaller gap sizes. In contrast, thermosets, due to their crosslinked nature, were less sensitive to laser power and scan speed, offering a wider processing window with less degradation. Multiple scans increased heat absorption in polymers, such that all polymers degraded below a gap size of 0.5 mm. This study provides insights into preserving polymers during integrated processing with ceramic components, expanding the design possibilities for dissimilar materials in MMAM.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"150 ","pages":"Pages 1153-1163"},"PeriodicalIF":6.1,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144588666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental and data-driven exploration of surface topography and tribological properties of additively manufactured polymers using fused filament fabrication (FFF)","authors":"Samsul Mahmood ,&nbsp;Emily Guo ,&nbsp;Abdullah Al Nahian ,&nbsp;Shoumik Sadaf ,&nbsp;Zhihua Jiang ,&nbsp;Lauren Beckingham ,&nbsp;Kyle Schulze","doi":"10.1016/j.jmapro.2025.06.088","DOIUrl":"10.1016/j.jmapro.2025.06.088","url":null,"abstract":"<div><div>Additive manufacturing (AM) has revolutionized rapid prototyping and manufacturing. However, limited research has been done on the effect of build orientation and surface roughness on AM parts’ frictional and wear characteristics. This study examines how different print and system parameters influence the surface topography and tribological behavior of 3D printed PLA. The samples were printed in three orientations and tested under varying normal loads (50–100 N). The vertically printed samples resulted in the best wear performance compared to the other two build orientations (<span><math><mo>∼</mo></math></span> 26.75% and 18.47%, respectively, at 100 N normal load). The coefficient of friction also showed dependency on the orientation of the print. The effect of surface topography parameters on tribological properties was also investigated. Skewness, <span><math><msub><mrow><mi>S</mi></mrow><mrow><mi>s</mi><mi>k</mi></mrow></msub></math></span>, and maximum valley depth, <span><math><msub><mrow><mi>S</mi></mrow><mrow><mi>v</mi></mrow></msub></math></span>, exhibited a strong positive correlation with the coefficient of friction, indicating that tribological behaviors are more sensitive to extreme surface topography features than average surface roughness (<span><math><msub><mrow><mi>S</mi></mrow><mrow><mi>a</mi></mrow></msub></math></span>). A data-driven approach was employed to predict wear rate and coefficient of friction using four machine learning models: Support Vector Regression (SVR), Artificial Neural Network (ANN), Random Forest (RF), and Extreme Gradient Boosting (XGBoost), where decision tree-based models outperformed others. The RF model achieved an <span><math><msup><mrow><mi>R</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span> value of 0.98 in predicting the wear rate and the coefficient of friction, where surface roughness parameters and operational parameters (normal loads, sliding distance) played critical roles.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"150 ","pages":"Pages 1132-1152"},"PeriodicalIF":6.1,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144580398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel method for suppressing clogging of nozzle and stopper rod by electric current pulse during continuous casting of ultra-low carbon steel","authors":"Kaiwang Chen ,&nbsp;Dongxue Wang ,&nbsp;Lei Yuan ,&nbsp;Qiang Gu ,&nbsp;Guoqi Liu ,&nbsp;Hongxia Li","doi":"10.1016/j.jmapro.2025.07.029","DOIUrl":"10.1016/j.jmapro.2025.07.029","url":null,"abstract":"<div><div>The effect of electric current pulse (ECP) on the clogging behavior of submerged entry nozzle (SEN) and stopper rod was studied during the continuous casting process of ultra-low carbon steel. Compared to normal treatment of SEN, ECP effectively prevented the deposition of alumina (Al₂O₃) inclusions at the nozzle outlet and stopper rod tip. Specifically, the application of ECP reduced the clogging thickness by more than 21 %, and the adhesion at the tip was mainly the tundish covering flux. Under ECP, the clogging density increased, which reduced the detachment of large-sized inclusions. Notably, the lattice distortions and dislocations of Al₂O₃ on the surface of the auxiliary electrode (negative electrode) increased its conductivity at high temperature. Furthermore, the mold level fluctuation and the change in inclusion size in the slab also showed that ECP could effectively suppress the clogging behavior, thereby enhancing the slab quality. This novel study provides important reference value and practical significance for applying external fields to suppress clogging of SEN and stopper rod.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"151 ","pages":"Pages 1-23"},"PeriodicalIF":6.1,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144604811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Properties of composite micro-textured surface on YG8 cemented carbide prepared by laser peening and ablation","authors":"Yang Lu ,&nbsp;Xiangqian Liu ,&nbsp;Jing Guo ,&nbsp;Changan Zhou","doi":"10.1016/j.jmapro.2025.07.015","DOIUrl":"10.1016/j.jmapro.2025.07.015","url":null,"abstract":"<div><div>This paper proposes a novel method for fabricating composite micro-textured surfaces using a combined laser processing technique. The method integrates laser peening without coating and laser ablation texturing in the air to create composite micro-textured surfaces on YG8 cemented carbide. The study examines the microstructure, roughness, hardness, residual stress, friction-wear performance, and cutting performance of composite micro-textured surfaces. Experimental results indicate that laser treatment significantly alters the microstructure and surface properties of cemented carbide. In particular, the composite micro-textured surface (LP-T) achieved by combining laser peening and ablation, demonstrated the highest surface hardness (1579 HV). It also shows an improved surface contact ratio and a balanced residual stress distribution (231.8 MPa). The average friction coefficient was the lowest, reduced by 19.4 % compared to traditional polished surfaces. Additionally, the composite treatment significantly lowers cutting force and temperature at higher cutting speeds, improving adhesive wear on the cutting face. In conclusion, the laser composite treatment substantially enhances the performance of cemented carbide by optimizing its surface characteristics.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"150 ","pages":"Pages 1118-1131"},"PeriodicalIF":6.1,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144580396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Abnormal melt pool behavior in overhead wire arc-based directed energy deposition","authors":"Hongbo Liu,&nbsp;Hui Chen,&nbsp;Jun Xiong","doi":"10.1016/j.jmapro.2025.07.020","DOIUrl":"10.1016/j.jmapro.2025.07.020","url":null,"abstract":"<div><div>Overhead wire arc-based directed energy deposition (WADED) is a key technique for the in-situ fabrication of overhanging components. However, humping and dripping frequently occur during overhead WADED since gravity acting on the melt pool may make it detach from previous layers. This study investigates gravity-induced humping and dripping phenomena in overhead WADED of thin-walled low-carbon steel parts. The droplet transfer behavior of four gas metal arc (GMA) variants, i.e., continuous current GMA (CC-GMA), cold metal transfer (CMT), pulsed GMA (P-GMA), and CMT plus pulse (CMT + P), is comparatively analyzed during overhead deposition. Among the four variants, CMT + P can produce the best forming quality due to its highly stable droplet transfer. The melt pool geometry ratio <em>D</em>, defined as the product of melt pool length and height divided by the square of melt pool width, is proposed as an index to evaluate the probability of humping and dripping defects. A process window for overhead WADED using the CMT + P process is established. The effects of travel speed (TS), wire feed speed (WFS), and a constant WFS/TS ratio on the melt pool behavior during overhead deposition are explored. When <em>D</em> is below 2.0, stable melt pools and defect-free surfaces are produced. When <em>D</em> is greater than or equal to 2.0 but &lt;3.9, humping is more likely to form with increasing TS or WFS. Dripping occurs when <em>D</em> is greater than or equal to 3.9, especially at lower TS or higher WFS. When the WFS/TS ratio is kept constant, humping and dripping defects occur more easily as WFS and the corresponding TS increase. This study lays a solid foundation for defect-free overhead WADED of complex overhanging structures.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"150 ","pages":"Pages 1164-1177"},"PeriodicalIF":6.1,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144588667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of tailored softening behavior of aluminized boron steel (22MnB5) in hot stamping process using die surface relief patterns","authors":"Jea-Myoung Park ,&nbsp;Seong-Guk Son ,&nbsp;Kye-Jeong Park ,&nbsp;Je-Youl Kong ,&nbsp;Seung-Chae Yoon","doi":"10.1016/j.jmapro.2025.06.067","DOIUrl":"10.1016/j.jmapro.2025.06.067","url":null,"abstract":"<div><div>The hot stamping process is widely utilized in the global automotive industry for the fabrication of body components, due to its effectiveness in achieving both lightweight structures and crash safety performance. Typically, aluminized 22MnB5 material is predominantly employed, enabling the attainment of a strength of 1.5 GPa. However, producing finished parts through hot stamping requires laser trimming, which results in increased energy costs and extended production times. Efforts to resolve these issues by adopting mechanical trimming have been made, yet achieving a high-quality sheared surface with mechanical trimming remains difficult. Although techniques involving localized softening have been proposed to address this challenge, they necessitate additional costs and investments in equipment. In this study, relief patterns (RPs) were applied to the surface of the hot stamping die to create air pockets, thereby regulating the quenching rate to achieve localized softening. This method aimed to observe the resultant changes in mechanical properties and to assess the mechanical shear performance and quality improvement of components subjected to the hot stamping process. The experimental results indicated an increase in the burnish ratio of the sheared surface and an improvement in micro-cracks on the fracture surface. By employing RPs, approximately 10 % localized softening of mechanical strength was achieved, V-bending was enhanced by approximately 25 %, and the entrapped hydrogen content was reduced by approximately 32 %. These outcomes are expected to significantly contribute to improving the efficiency and quality of the hot stamping process, as well as reducing carbon emissions.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"150 ","pages":"Pages 1097-1107"},"PeriodicalIF":6.1,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144580394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance-oriented layout optimization of a multi-spindle drilling cell for acoustic liners in aero-engine nacelles","authors":"Haoyu Tian ,&nbsp;Biao Mei ,&nbsp;Yun Fu ,&nbsp;Yongtai Yang ,&nbsp;Weidong Zhu","doi":"10.1016/j.jmapro.2025.06.107","DOIUrl":"10.1016/j.jmapro.2025.06.107","url":null,"abstract":"<div><div>Laying acoustic liners is one of the most effective ways to reduce aero-engine noise. Traditional single-spindle drilling systems are inadequate for high-quality and efficient drilling for large-scale sound-absorbing holes on acoustic liners. Therefore, this paper develops a robotic multi-spindle drilling cell (RMDCell) that integrates a multi-spindle drilling end-effector, a standard industrial robot, and a rotatable clamping fixture. A robot performance-oriented layout optimization method is studied for the RMDCell to improve the drilling quality of acoustic liners in aero-engine nacelles. Firstly, a weighted comprehensive performance model of the multi-spindle drilling robot is built, integrating joint limit avoidance, singularity avoidance, and robot stiffness performances. Thereinto, a new robot stiffness performance index is introduced, and a variable robot stiffness weight is derived considering the end-effector's spindle configuration. Secondly, a dimensionality reduction method of layout optimization parameters and a drilling zone division method are proposed for the RMDCell of nacelle acoustic liners. A bi-level optimization algorithm for RMDCell layout parameters is developed. The algorithm fuses particle swarm optimization (PSO) and deep hierarchical feature learning on point sets in a metric space (PointNet++). Finally, drilling experiments are conducted based on the developed RMDCell. The results show that the comprehensive robot performance index is reduced by 39.8 % after optimization compared to the comprehensive robot performance before layout optimization. The layout optimization method effectively reduces defects such as burrs, delamination, and tearing in composite sound-absorbing holes. The average delamination factor decreases by 16.5 %. The robot performance-oriented layout optimization significantly improves the drilling quality, which meets the manufacturing quality requirements of the acoustic liner of an aero-engine nacelle.</div></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":"150 ","pages":"Pages 1080-1096"},"PeriodicalIF":6.1,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144580393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}