The distributed and customized 3D printing can be realized by 3D printing services in a cloud manufacturing environment.As a growing number of 3D printers are becoming accessible on various 3D printing service platfor...The distributed and customized 3D printing can be realized by 3D printing services in a cloud manufacturing environment.As a growing number of 3D printers are becoming accessible on various 3D printing service platforms,there raises the concern over the validation of virtual product designs and their manufacturing procedures for novices as well as users with 3D printing experience before physical products are produced through the cloud platform.This paper presents a 3D model to help users validate their designs and requirements not only in the traditional digital 3D model properties like shape and size,but also in physical material properties and manufacturing properties when producing physical products like surface roughness,print accuracy and part cost.These properties are closely related to the process of 3D printing and materials.In order to establish the 3D model,the paper analyzes the model of the 3D printing process selection in the cloud platform.Triangular intuitionistic fuzzy numbers are applied to generate a set of 3D printers with the same process and material.Based on the 3D printing process selection model,users can establish the 3D model and validate their designs and requirements on physical material properties and manufacturing properties before printing physical products.展开更多
Al electrodes are well known as ohmic contact electrodes for the PTC component , the influence of their thickness on final component properties was investigated by comparing their ohmic characteristics with the ones ...Al electrodes are well known as ohmic contact electrodes for the PTC component , the influence of their thickness on final component properties was investigated by comparing their ohmic characteristics with the ones of InGa electrodes . After observing the Al paste physical and chemical behaviors during rising temperature by thermal analysis (DTA), the firing operation of Al electrodes could be divided into three main subsections: the temperature rising time (t-r), the peak firing temperature (T-p) and the hold time at peak firing temperature (t-h). The effects of these three parameters on final component properties were discussed in detail.展开更多
In this study, indoor air quality (IAQ) assessments were carried out in a screen printing facility. The air sampling was conducted in press department, including two different types of screen printing machines: sem...In this study, indoor air quality (IAQ) assessments were carried out in a screen printing facility. The air sampling was conducted in press department, including two different types of screen printing machines: semi-automatic and automatic. Air samples were collected and analyzed in situ for 4 times, once per 2 hours, during working time of 8 hours. Analysis of the experimental data showed that ambient ozone concentrations slowly increases with the increasing of TVOCs concentration and intensive use of UV lamps during automatic screen printing process. Therefore, the detected concentration levels of ozone and VOCs were compared with the Occupational Safety and Health Administration (OSHA) and Serbian Regulation. Comparison of the two mentioned standard regulations, the ozone concentrations in indoor printing air were from 0.83 to 8.1 and 2.4 to 16.2 times higher in the relation to the prescribed PEL and maximum allowed concentration (MAC) values, respectively, while the concentrations of particular VOCs were much below the PEL prescribed by the OSHA.展开更多
This paper describes the preparation and properties of TiN_x-SiO_2 double-layered antireflective(AR) coatings that were applied with print process. The coating material was analyzed and TiN_x was used instead of TiO_2...This paper describes the preparation and properties of TiN_x-SiO_2 double-layered antireflective(AR) coatings that were applied with print process. The coating material was analyzed and TiN_x was used instead of TiO_2 as high refractive material. The influence of solution concentration on AR property was studied. The testing result shows that the coatings using print process are featured with excellent mechanical property and the AR property is comparable to American Southwall AR product. It is expected that the study would promote the industrialization progress in AR coatings.展开更多
This study investigated the resilience of traditional concrete dams compared to 3D printed concrete dams(3DPC)when subjected to debris flow.Three types of dams,namely check dams,arch dams,and curve dams,were numerical...This study investigated the resilience of traditional concrete dams compared to 3D printed concrete dams(3DPC)when subjected to debris flow.Three types of dams,namely check dams,arch dams,and curve dams,were numerically analyzed using a three-dimensional Coupled Eulerian-Lagrangian(CEL)methodology.The research focused on critical factors such as impact force and viscous energy dissipation to compare dam performance.Additionally,the study examined the printing and service phases of 3DPC models,determining potential failure modes and analyzing printing parameters.The results demonstrated that 3DPC dams outperformed traditional concrete dams,with filament deposition orientation,perpendicular to the debris flow direction,identified as a pivotal factor.Infill percentage and pattern were also found to influence the behavior of 3DPC models.Notably,curved dams exhibited superior performance based on dam geometry.These findings have significant potential for advancing the development of resilient dam structures capable of withstanding debris flow impacts.展开更多
Miniaturization and flexibility are becoming the trend in the development of electronic products. These key features are driving new methods in the manufacturing of such products. Printed electronics technology is a n...Miniaturization and flexibility are becoming the trend in the development of electronic products. These key features are driving new methods in the manufacturing of such products. Printed electronics technology is a novel additive manufacturing technique that uses active inks to print onto a diverse set of substrates, realizing large-area, low-cost, flexible and green manufacturing of electronic products. These advantageous properties make it extremely compatible with flexible electronics fabrication and extend as far as offering revolutionary methods in the production of flexible electronic devices. In this paper, the details of a printing process system are introduced, including the materials that can be employed as inks, common substrates, and the most recently reported printing strategies. An assessment of future setbacks and developments of printed flexible electronics is also presented.展开更多
In order to study the hot melt extrusion process in fused deposition modeling(FDM),this study mainly explores the effects of printing temperature,heated block length,feeding speed on the exit morphology and mechanical...In order to study the hot melt extrusion process in fused deposition modeling(FDM),this study mainly explores the effects of printing temperature,heated block length,feeding speed on the exit morphology and mechanical properties of FDM printed Polylactic acid(PLA)samples.High-speed camera is used to capture the exit morphology of molten PLA just extruded to the nozzle.According to exit morphology,the outlet states of extruded molten material can be divided into four categories,namely,bubbled state,coherent state,expanding state,and unstable state.Tensile test results show that printing temperature,heated block length and printing speed have significant influence on tensile properties and fracture mode of FDM printed samples.When the heated block length is 15 mm and 30 mm,there is a ductile-brittle transition in fracture mode with the increase of printing speed.The printing process window under different heated block lengths and printing temperatures has been figured out and the distribution of printing process window under different printing speeds has been discussed.There is a maximum printing process window under the heated block length of 30 mm.This finding provides a frame work for performance prediction of FDM printed parts and theoretical guidance for expanding the scope of printing process window.展开更多
The simultaneous removal of ethyl acetate, benzene and toluene with relatively low or high initial concentration is studied using a laboratory scale gliding arc gas discharge (GA) reactor. Good decomposition efficienc...The simultaneous removal of ethyl acetate, benzene and toluene with relatively low or high initial concentration is studied using a laboratory scale gliding arc gas discharge (GA) reactor. Good decomposition efficiencies are obtained which proves that the GA is effective for the treatment of volatile organic compounds (VOCs) with either low or high concentration. A theoretical decomposition mechanism is proposed based on detection of the species in the plasma region and analysis of the decomposition by-products. This preliminary investigation reveals that the GA has potential to be applied to the treatment of exhaust air during color printing and coating works, by either direct removal or combination with activated carbon adsorption/desorption process.展开更多
Printing of metal bottom back electrodes of flexible organic solar cells(FOSCs) at low temperature is of great significance to realize the full-solution fabrication technology. However, this has been difficult to ac...Printing of metal bottom back electrodes of flexible organic solar cells(FOSCs) at low temperature is of great significance to realize the full-solution fabrication technology. However, this has been difficult to achieve because often the interfacial properties of those printed electrodes, including conductivity, roughness, work function,optical and mechanical flexibility, cannot meet the device requirement at the same time. In this work, we fabricate printed Ag and Cu bottom back cathodes by a low-temperature solution technique named polymer-assisted metal deposition(PAMD) on flexible PET substrates. Branched polyethylenimine(PEI) and ZnO thin films are used as the interface modification layers(IMLs) of these cathodes. Detailed experimental studies on the electrical, mechanical, and morphological properties, and simulation study on the optical properties of these IMLs are carried out to understand and optimize the interface of printed cathodes. We demonstrate that the highest power conversion efficiency over 3.0% can be achieved from a full-solution processed OFSC with the device structure being PAMDAg/PEI/P3 HT:PC61BM/PH1000. This device also acquires remarkable stability upon repeating bending tests.展开更多
基金the National High-Tech Research and Development Plan of China under Grant No.2015AA042101 and Fund of State Key Laboratory of Intelligent Manufacturing System Technology in China.
文摘The distributed and customized 3D printing can be realized by 3D printing services in a cloud manufacturing environment.As a growing number of 3D printers are becoming accessible on various 3D printing service platforms,there raises the concern over the validation of virtual product designs and their manufacturing procedures for novices as well as users with 3D printing experience before physical products are produced through the cloud platform.This paper presents a 3D model to help users validate their designs and requirements not only in the traditional digital 3D model properties like shape and size,but also in physical material properties and manufacturing properties when producing physical products like surface roughness,print accuracy and part cost.These properties are closely related to the process of 3D printing and materials.In order to establish the 3D model,the paper analyzes the model of the 3D printing process selection in the cloud platform.Triangular intuitionistic fuzzy numbers are applied to generate a set of 3D printers with the same process and material.Based on the 3D printing process selection model,users can establish the 3D model and validate their designs and requirements on physical material properties and manufacturing properties before printing physical products.
文摘Al electrodes are well known as ohmic contact electrodes for the PTC component , the influence of their thickness on final component properties was investigated by comparing their ohmic characteristics with the ones of InGa electrodes . After observing the Al paste physical and chemical behaviors during rising temperature by thermal analysis (DTA), the firing operation of Al electrodes could be divided into three main subsections: the temperature rising time (t-r), the peak firing temperature (T-p) and the hold time at peak firing temperature (t-h). The effects of these three parameters on final component properties were discussed in detail.
文摘In this study, indoor air quality (IAQ) assessments were carried out in a screen printing facility. The air sampling was conducted in press department, including two different types of screen printing machines: semi-automatic and automatic. Air samples were collected and analyzed in situ for 4 times, once per 2 hours, during working time of 8 hours. Analysis of the experimental data showed that ambient ozone concentrations slowly increases with the increasing of TVOCs concentration and intensive use of UV lamps during automatic screen printing process. Therefore, the detected concentration levels of ozone and VOCs were compared with the Occupational Safety and Health Administration (OSHA) and Serbian Regulation. Comparison of the two mentioned standard regulations, the ozone concentrations in indoor printing air were from 0.83 to 8.1 and 2.4 to 16.2 times higher in the relation to the prescribed PEL and maximum allowed concentration (MAC) values, respectively, while the concentrations of particular VOCs were much below the PEL prescribed by the OSHA.
文摘This paper describes the preparation and properties of TiN_x-SiO_2 double-layered antireflective(AR) coatings that were applied with print process. The coating material was analyzed and TiN_x was used instead of TiO_2 as high refractive material. The influence of solution concentration on AR property was studied. The testing result shows that the coatings using print process are featured with excellent mechanical property and the AR property is comparable to American Southwall AR product. It is expected that the study would promote the industrialization progress in AR coatings.
基金supported by the National Natural Science Foundation of China(Grant no.42207232)the Sichuan Science and Technology Plan Project(2023YFS0444)+1 种基金the Transportation Technology Project of Sichuan Province(2021-A-04)the State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Independent Research Project(SKLGP2021Z001,SKLGP2022Z023)。
文摘This study investigated the resilience of traditional concrete dams compared to 3D printed concrete dams(3DPC)when subjected to debris flow.Three types of dams,namely check dams,arch dams,and curve dams,were numerically analyzed using a three-dimensional Coupled Eulerian-Lagrangian(CEL)methodology.The research focused on critical factors such as impact force and viscous energy dissipation to compare dam performance.Additionally,the study examined the printing and service phases of 3DPC models,determining potential failure modes and analyzing printing parameters.The results demonstrated that 3DPC dams outperformed traditional concrete dams,with filament deposition orientation,perpendicular to the debris flow direction,identified as a pivotal factor.Infill percentage and pattern were also found to influence the behavior of 3DPC models.Notably,curved dams exhibited superior performance based on dam geometry.These findings have significant potential for advancing the development of resilient dam structures capable of withstanding debris flow impacts.
文摘Miniaturization and flexibility are becoming the trend in the development of electronic products. These key features are driving new methods in the manufacturing of such products. Printed electronics technology is a novel additive manufacturing technique that uses active inks to print onto a diverse set of substrates, realizing large-area, low-cost, flexible and green manufacturing of electronic products. These advantageous properties make it extremely compatible with flexible electronics fabrication and extend as far as offering revolutionary methods in the production of flexible electronic devices. In this paper, the details of a printing process system are introduced, including the materials that can be employed as inks, common substrates, and the most recently reported printing strategies. An assessment of future setbacks and developments of printed flexible electronics is also presented.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.11502269 and 11672304)plan of Beijing Municipal Commission of Science and Technology(Grant No.Z181100003818015).
文摘In order to study the hot melt extrusion process in fused deposition modeling(FDM),this study mainly explores the effects of printing temperature,heated block length,feeding speed on the exit morphology and mechanical properties of FDM printed Polylactic acid(PLA)samples.High-speed camera is used to capture the exit morphology of molten PLA just extruded to the nozzle.According to exit morphology,the outlet states of extruded molten material can be divided into four categories,namely,bubbled state,coherent state,expanding state,and unstable state.Tensile test results show that printing temperature,heated block length and printing speed have significant influence on tensile properties and fracture mode of FDM printed samples.When the heated block length is 15 mm and 30 mm,there is a ductile-brittle transition in fracture mode with the increase of printing speed.The printing process window under different heated block lengths and printing temperatures has been figured out and the distribution of printing process window under different printing speeds has been discussed.There is a maximum printing process window under the heated block length of 30 mm.This finding provides a frame work for performance prediction of FDM printed parts and theoretical guidance for expanding the scope of printing process window.
基金Project (No. 50476058) supported by the National Natural ScienceFoundation of China
文摘The simultaneous removal of ethyl acetate, benzene and toluene with relatively low or high initial concentration is studied using a laboratory scale gliding arc gas discharge (GA) reactor. Good decomposition efficiencies are obtained which proves that the GA is effective for the treatment of volatile organic compounds (VOCs) with either low or high concentration. A theoretical decomposition mechanism is proposed based on detection of the species in the plasma region and analysis of the decomposition by-products. This preliminary investigation reveals that the GA has potential to be applied to the treatment of exhaust air during color printing and coating works, by either direct removal or combination with activated carbon adsorption/desorption process.
基金supported by the Research Grant Council of Hong Kong(No.PolyUC5015-15G)the Hong Kong Polytechnic University(No.G-SB06)the National Natural Science Foundation of China(Nos.21125316,21434009,51573026)
文摘Printing of metal bottom back electrodes of flexible organic solar cells(FOSCs) at low temperature is of great significance to realize the full-solution fabrication technology. However, this has been difficult to achieve because often the interfacial properties of those printed electrodes, including conductivity, roughness, work function,optical and mechanical flexibility, cannot meet the device requirement at the same time. In this work, we fabricate printed Ag and Cu bottom back cathodes by a low-temperature solution technique named polymer-assisted metal deposition(PAMD) on flexible PET substrates. Branched polyethylenimine(PEI) and ZnO thin films are used as the interface modification layers(IMLs) of these cathodes. Detailed experimental studies on the electrical, mechanical, and morphological properties, and simulation study on the optical properties of these IMLs are carried out to understand and optimize the interface of printed cathodes. We demonstrate that the highest power conversion efficiency over 3.0% can be achieved from a full-solution processed OFSC with the device structure being PAMDAg/PEI/P3 HT:PC61BM/PH1000. This device also acquires remarkable stability upon repeating bending tests.