International Thermal Spray Conference最新文献

Cold Spray Deposition of Aluminium 6061 Decorated with Al2O3 Nanoparticles Al2O3纳米颗粒修饰铝6061的冷喷涂沉积

International Thermal Spray Conference Pub Date : 2023-05-22 DOI: 10.31399/asm.cp.itsc2023p0574

B. Marzbanrad, E. Marzbanrad, H. Jahed

引用次数: 0

Microstructural, Mechanical, and Tribological Evaluation of CuAl-Based Coatings Deposited by APS and HVOF APS和HVOF沉积cual基涂层的显微组织、力学和摩擦学评价

International Thermal Spray Conference Pub Date : 2023-05-22 DOI: 10.31399/asm.cp.itsc2023p0046

C. Bidmeshki, A. Liberati, A. Roy, F. Ben Ettouil, C. Moreau, A. I. Encalada, S. A. Alidokht, R. Chromik, P. Stoyanov

{"title":"Microstructural, Mechanical, and Tribological Evaluation of CuAl-Based Coatings Deposited by APS and HVOF","authors":"C. Bidmeshki, A. Liberati, A. Roy, F. Ben Ettouil, C. Moreau, A. I. Encalada, S. A. Alidokht, R. Chromik, P. Stoyanov","doi":"10.31399/asm.cp.itsc2023p0046","DOIUrl":"https://doi.org/10.31399/asm.cp.itsc2023p0046","url":null,"abstract":"\u0000 Thermal-sprayed coatings have been extensively used in aerospace with the main purpose to overcome critical challenges such as abrasive wear, corrosion, and erosion under high temperatures and pressures. Such protective coatings can also play a crucial role in optimizing the efficiency of gas turbine engines and therefore in reducing fuel consumption and CO2 emissions. CuAl-based thermal sprayed coatings are commonly employed in tribological interfaces within gas turbine engines to improve the fretting wear resistance. These coatings are typically deposited by more traditional thermal spray techniques such as Air Plasma Spray (APS), which can result in high amounts of oxidation within the coating. The main purpose of this study is to critically evaluate lower temperature deposition techniques such as High Velocity Oxygen Fuel (HVOF). More specifically, commercially available Cu-10Al powders were deposited by APS and HVOF and compared in terms of their microstructural, mechanical properties, and tribological behavior at various temperatures. The results showed that the friction coefficient for both coatings was equivalent at room temperature while it was lower for the APS coating at high temperature. Similarly, the specific wear rates showed little difference between the different deposition processes at room temperature while the APS coating had a lower wear rate at elevated temperature when compared to the HVOF coating. The differences in the friction and wear behavior were attributed to differences in the interfacial processes.","PeriodicalId":114755,"journal":{"name":"International Thermal Spray Conference","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127379831","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}

引用次数: 0

Oxide Characterization of Copper Cold Spray Feedstock Powders with X-Ray Photoelectron Spectroscopy 用x射线光电子能谱法表征铜冷喷涂原料粉末的氧化物

International Thermal Spray Conference Pub Date : 2023-05-22 DOI: 10.31399/asm.cp.itsc2023p0091

C. Katsari, Yannis Kotsakis, S. Yue, B. Guerreiro, D. Poirier, J. Giallonardo

{"title":"Oxide Characterization of Copper Cold Spray Feedstock Powders with X-Ray Photoelectron Spectroscopy","authors":"C. Katsari, Yannis Kotsakis, S. Yue, B. Guerreiro, D. Poirier, J. Giallonardo","doi":"10.31399/asm.cp.itsc2023p0091","DOIUrl":"https://doi.org/10.31399/asm.cp.itsc2023p0091","url":null,"abstract":"\u0000 In conventional powder processing, there has been considerable work on classifying feedstock powders based on particle size distribution, morphology, microstructure and composition, since these influence processability and final properties. Cold spray is a new application for powders and conventional characterization may be insufficient to assess powder cold sprayability. In particular, metallic powders have an oxide layer, which breaks during impact with the substrate or with another coating layer during cold spray; this fragmentation facilitates bonding. It has been suggested that the thickness of the oxide layer can influence the mechanism of fragmentation; thicker oxides are easier to remove, revealing clean metal surfaces that can metallurgically bond. Consequently, not all high-purity powders or powders that are stored in ambient conditions have the potential to give good coating properties after cold-spray. This work focuses on surface oxidation of the powders, characterizing the variation of oxide film aspects with size and composition of nominally pure copper powders using X-ray Photoelectron Spectroscopy (XPS). The results indicate the presence of Cu (I) and Cu (II) oxide species on the surface of as-received, naturally aged and heat-treated powders; their thickness is determined using the depth profiling feature.","PeriodicalId":114755,"journal":{"name":"International Thermal Spray Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130320268","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}

引用次数: 0

Development and Characterization of Micro-Plasma Additive Manufacturing Process for Inconel 718 Superalloy Inconel 718高温合金微等离子体增材制造工艺的发展与表征

International Thermal Spray Conference Pub Date : 2023-05-22 DOI: 10.31399/asm.cp.itsc2023p0450

J. Nagy, Adrian Singh, Xiao Huang

{"title":"Development and Characterization of Micro-Plasma Additive Manufacturing Process for Inconel 718 Superalloy","authors":"J. Nagy, Adrian Singh, Xiao Huang","doi":"10.31399/asm.cp.itsc2023p0450","DOIUrl":"https://doi.org/10.31399/asm.cp.itsc2023p0450","url":null,"abstract":"\u0000 A micro-plasma system was investigated for its capability in additive manufacturing (AM). Micro-plasma AM system has the advantage of lower cost and higher deposition rate over the laser-based AM systems, and generates leaner and cleaner weld deposit than other arc-based AM systems. However, the microplasma system is complex and involves a large number of process variables. In this study, the effects of two arc and wire feed modes on dimensional consistency and hardness were firstly examined. Subsequently, one set of the specimens was further subjected to oxidation tests and the results were compared to that from conventional wrought Inconel 718. It was found that all four processes could produce crack free samples without measurable distortion. Some surface discoloration was observed, ranging from light straw to a purple tint. After heat treatment, the hardness of the samples varies from 403 to 440 HV, with the transverse surface showing slightly lower hardness values. The oxidation tests at 900 °C yielded similar weight change for AM Inconel 718 and its counterpart wrought alloy; however, the rate constant for wrought alloy was slightly higher. Microstructural analysis with SEM and EDS revealed a dendritic structure in the AM Inconel 718 and the presence of Nb-rich compounds in the interdendritic region. The polycrystal grain structure was not delineated in AM material as that in wrought 718. With the increase of exposure time, the oxide layer continues to increase at a higher rate, along with a sublayer of Ni3Nb above the metal substrate. In addition, after 200 hours, the wrought alloy developed porous chromia, while AM material exhibited uneven oxide thickness. In consideration of all aspects of the evaluation carried out thus far, it is concluded that the AM material produced by micro-plasma process is equivalent to wrought material in mechanical properties and oxidation performance.","PeriodicalId":114755,"journal":{"name":"International Thermal Spray Conference","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116206168","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}

引用次数: 0

Adhesion of HVOF Sprayed Coatings on Laser Textured Steel and Ceramics Substrates HVOF喷涂涂层在激光织构钢和陶瓷基体上的附着力研究

International Thermal Spray Conference Pub Date : 2023-05-22 DOI: 10.31399/asm.cp.itsc2023p0519

M. Vostřák, Ž. Dlouhá, J. Duliškovič, L. Jarolímová, Š. Houdková, Jana Na’ová, O. Peters, J. Schille, U. Loeschner, J. Martan

{"title":"Adhesion of HVOF Sprayed Coatings on Laser Textured Steel and Ceramics Substrates","authors":"M. Vostřák, Ž. Dlouhá, J. Duliškovič, L. Jarolímová, Š. Houdková, Jana Na’ová, O. Peters, J. Schille, U. Loeschner, J. Martan","doi":"10.31399/asm.cp.itsc2023p0519","DOIUrl":"https://doi.org/10.31399/asm.cp.itsc2023p0519","url":null,"abstract":"\u0000 In thermal spraying, one of the fundamental elements to achieving good bonding strength of the applied coating is surface preparation. Traditionally grit blasting using hard particles such as corundum is used to achieve suitable roughness on the substrate. Lately, there is an effort to find a suitable alternative from ecological and economical aspects. A promising possibility is laser texturing which enables the preparation of defined structures on the surface. Within a research project, procedures are developed to texture various substrates to direct application of HVOF coatings. The main goal is to achieve speeds of texturing comparable to grit blasting – more than 500 mm2/s while ensuring good bonding strength of the applied coating. This study focuses on HVOF spraying of Stellite 6 and WC-CoCr Coating. Selected substrates are steel, and then materials that cannot be traditionally grit blasted – nitrided steel and alumina ceramics. The study presents the analysis of laser textures on substrates, analysis of coating substrate-coating interface, and adhesion tests by tensile test. The most suitable textures – regarding the processing speed and achieved adhesion are selected.","PeriodicalId":114755,"journal":{"name":"International Thermal Spray Conference","volume":"121 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126411900","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}

引用次数: 0

Development of a Duplex Sn-Cu Coating on Carbon Fiber-Reinforced Polymers (CFRPs) using Cold Spray and Electrodeposition Processes 采用冷喷涂和电沉积技术在碳纤维增强聚合物(CFRPs)表面制备双相Sn-Cu涂层

International Thermal Spray Conference Pub Date : 2023-05-22 DOI: 10.31399/asm.cp.itsc2023p0208

Panteha Fallah, S. Yue, A. McDonald

{"title":"Development of a Duplex Sn-Cu Coating on Carbon Fiber-Reinforced Polymers (CFRPs) using Cold Spray and Electrodeposition Processes","authors":"Panteha Fallah, S. Yue, A. McDonald","doi":"10.31399/asm.cp.itsc2023p0208","DOIUrl":"https://doi.org/10.31399/asm.cp.itsc2023p0208","url":null,"abstract":"\u0000 Direct cold spray deposition of Cu was not possible on carbon fiber-reinforced polymer composites (CFRPs) with thermosetting polymer as the matrix material due to substrate erosion. In a recent study, an epoxy-CFRP was successfully metallized through a hybrid coating process that involves three consecutive coating steps: (i) electroless deposition, followed by (ii) electrodeposition, and finally (iii) cold spray. In this present study, for the reduction of the coating process steps, a duplex metallic coating was developed on an epoxy-CFRPs by cold spray deposition of tin (Sn) to fabricate a continuous metallic interlayer, followed by Cu electrodeposition (i.e., SnCS-CuEP). The tensile adhesion bond strength and the electrical resistivity of the duplex coating were investigated. It was found that cold-sprayed Sn coating failed adhesively in the absence of the electrodeposited Cu coating. After the electrodeposition of Cu, cohesive failure of the cold-sprayed Sn coating took place. A “dissolution-deposition” mechanism has been established to explain the cohesive failure of the coldsprayed Sn coating after electrodeposition. The cohesive strength of the Sn coating is slightly higher than that of the previously fabricated three-step coating system. The electrical conductivity of the electrodeposited Cu coating was found to be 90% of bulk Cu. These results suggest that a duplex SnCS-CuEP coating can be fabricated on epoxy-CFRPs with relatively high electrical conductivity and slightly enhanced adhesion properties as compared to multilayered coatings fabricated using a three-step electroless deposition-electrodeposition-cold spray process.","PeriodicalId":114755,"journal":{"name":"International Thermal Spray Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130063242","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}

引用次数: 0

Cost-Effective UHVOF-Sprayed Coatings for the Wear Protection of Valves 用于阀门磨损保护的具有成本效益的uhvof喷涂涂层

International Thermal Spray Conference Pub Date : 2023-05-22 DOI: 10.31399/asm.cp.itsc2023p0480

K. Bobzin, H. Heinemann, E. Burbaum, M. Schulz

{"title":"Cost-Effective UHVOF-Sprayed Coatings for the Wear Protection of Valves","authors":"K. Bobzin, H. Heinemann, E. Burbaum, M. Schulz","doi":"10.31399/asm.cp.itsc2023p0480","DOIUrl":"https://doi.org/10.31399/asm.cp.itsc2023p0480","url":null,"abstract":"\u0000 Thermally sprayed WC/CoCr coatings are the most established coatings in the valve industry. However, due to the high wear resistance and as-sprayed surface roughness, the surface post processing costs are very high. Near-net-shaped fine powder coatings have the possibility to reduce the costs effectively. Due to the high specific surface to volume ratio of the powders, undesired phase transformations can occur during the spraying process. To avoid such phase transformations, the novel thermal spraying process Ultra-HVOF (UHVOF) is used in this study. An extensive parameter study is carried out on the influences of the process parameters on microhardness, porosity, as-sprayed surface roughness, phase composition and wear resistance. With suitable process parameters, near-netshaped and almost pore-free coatings can be applied. Compared to a conventional HVOF sprayed WC/CoCr coating, a wear reduction by a factor of three can be achieved in a pin-on-disktest against Al2O3 at a load of F = 15 N. Due to the pore-free and highly wear-resistant coatings, significantly thinner coatings can be used for the protection against corrosion and wear in valves. In addition, the required surface quality of the near-net-shape coatings can be achieved by polishing only. Thus, the novel UHVOF coatings represent a cost-effective alternative to conventionally used valve coatings.","PeriodicalId":114755,"journal":{"name":"International Thermal Spray Conference","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127618141","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}

引用次数: 0

Oxidation of In-flight Particles During HVAF—A Numerical Study hvaf过程中飞行颗粒氧化的数值研究

International Thermal Spray Conference Pub Date : 2023-05-22 DOI: 10.31399/asm.cp.itsc2023p0610

Sokhna Awa Bousso Diop, C. Moreau, Aleksandra Nasti, A. Dolatabad

{"title":"Oxidation of In-flight Particles During HVAF—A Numerical Study","authors":"Sokhna Awa Bousso Diop, C. Moreau, Aleksandra Nasti, A. Dolatabad","doi":"10.31399/asm.cp.itsc2023p0610","DOIUrl":"https://doi.org/10.31399/asm.cp.itsc2023p0610","url":null,"abstract":"\u0000 Oxygen present in the High Velocity Air-Fuel (HVAF) process can react with the in-flight metallic particles and cause their oxidation. A grown brittle oxide shell on metallic microsize particles can reduce their deposition efficiency and impair the coating final deposited properties/microstructure. In the current study, the oxide growth of MCrAlY particles, where M stands for Ni and Co, during their flight in the HVAF process has been modeled using the particle tracking scheme. A comprehensive theoretical oxide layer growth background is presented and used to track the particle oxidation process. The oxidation development includes the Mott-Cabrera theory for very thin films, which is function of the particle surrounding temperature and oxygen partial pressure. The very thin film regime, applicable under a limiting thickness, is defined based on the electric field present across the growing oxide layer. As the electric field decreases with oxide thickness, the oxidation rate is determined by thermal diffusion. The obtained results provide a correlation between HVAF system design and surface oxidation phenomena while offering a clear description of different oxidation stages.","PeriodicalId":114755,"journal":{"name":"International Thermal Spray Conference","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123682112","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}

引用次数: 0

Comparative Corrosion Behaviour of Cold Sprayed Titanium/Hydroxyapatite and Titanium/Baghdadite Composite Coatings in Simulated Body Fluid Environment 冷喷涂钛/羟基磷灰石和钛/巴格达石复合涂层在模拟体液环境中的腐蚀行为比较

International Thermal Spray Conference Pub Date : 2023-05-22 DOI: 10.31399/asm.cp.itsc2023p0487

Avneesh Kumar, Teekam Chand, R. Kant, Harpreet Singh

{"title":"Comparative Corrosion Behaviour of Cold Sprayed Titanium/Hydroxyapatite and Titanium/Baghdadite Composite Coatings in Simulated Body Fluid Environment","authors":"Avneesh Kumar, Teekam Chand, R. Kant, Harpreet Singh","doi":"10.31399/asm.cp.itsc2023p0487","DOIUrl":"https://doi.org/10.31399/asm.cp.itsc2023p0487","url":null,"abstract":"\u0000 Bioceramics deposition on medical devices is a widespread area of research for biomedical industries since such deposits can induce excellent chemical and biological properties to the devices. Thermal spraying has been a popular choice for developing coatings to enhance the mechanical, chemical, and biological responses of medical devices. However, the high heat involved during the thermal spraying of bioceramics limits their functionality. In this context, low processing temperature in cold spraying is believed to protect the bioceramics from degradation. However, depositing bioceramics using cold spray and achieving good mechanical properties are still challenging tasks because of their poor ductility. Therefore, bio metal matrix composites with reinforced bioceramics produced using cold spray are expected to give good mechanical, chemical, and biological properties. The present work presents deposition and microstructural characterization of titanium/hydroxyapatite (Ti/HA) and titanium/baghdadite (Ti/BAG) composite coatings by cold spraying. Furthermore, the comparative corrosion response of these coatings under a simulated body fluid environment is reported. The effect of laser remelting on microstructure and corrosion behavior is also discussed.","PeriodicalId":114755,"journal":{"name":"International Thermal Spray Conference","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129463181","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}

引用次数: 0

Effect of Spray Parameters on MCrAlY In-Flight Particle Oxidation and Coating Microstructure Deposited by Internal Diameter High Velocity Air Fuel (ID-HVAF) 喷射参数对MCrAlY飞行颗粒氧化及内径高速空气燃料(ID-HVAF)沉积涂层微观结构的影响

International Thermal Spray Conference Pub Date : 2023-05-22 DOI: 10.31399/asm.cp.itsc2023p0640

M. S. Lamana, A. K. Thoutam, A. Mahdavi, A. Liberati, F. Ben Ettouil, C. Moreau, A. Dolatabadi

{"title":"Effect of Spray Parameters on MCrAlY In-Flight Particle Oxidation and Coating Microstructure Deposited by Internal Diameter High Velocity Air Fuel (ID-HVAF)","authors":"M. S. Lamana, A. K. Thoutam, A. Mahdavi, A. Liberati, F. Ben Ettouil, C. Moreau, A. Dolatabadi","doi":"10.31399/asm.cp.itsc2023p0640","DOIUrl":"https://doi.org/10.31399/asm.cp.itsc2023p0640","url":null,"abstract":"\u0000 Aircraft gas turbine blades operate in aggressive, generally oxidizing, atmospheres. A solution to mitigate the degradation and improve the performance of such components is the deposition of thermal barrier coatings (TBCs). Specifically for bond coats in aerospace applications, High Velocity Air Fuel (HVAF) is very efficient for coating deposition. However, internal diameter (ID) HVAF has received little attention in the literature and could be a promising alternative to limit oxidation during spraying when compared to conventional methods. The main objective of this study is to analyze how the ID-HVAF process influences the microstructure of NiCoCrAlY coatings. To that end, an i7 ID-HVAF torch is used to deposit NiCoCrAlY splats on a steel substrate with different stand-off distances. The deposited splats showed the presence of craters, and both partially melted and deformed particles at the surface. The particle velocity data was recorded, and the splat deformation and amount of particles deposited was shown to be directly corelated to the stand-off distance. The material composition analyzed and quantified by Energy Dispersive Spectroscopy (EDS) did not reveal any traces of in-flight of particle oxidation, but further investigation is required. This study provided a preliminary understanding towards the importance of stand-off distance on the splat deformation and in-flight oxidation.","PeriodicalId":114755,"journal":{"name":"International Thermal Spray Conference","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129872031","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}

引用次数: 0