- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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The role of interfacial H-bonding in electrical properties of UV-cured resin filled with hydroxylated Al2O3 nanoparticles
摘要： Surface hydroxylation of crude Al2O3 (c-Al2O3) nanoparticles by H2O2 was conducted to tailor the electrical properties of UV-cured resin. The hydroxyl groups on Al2O3 particles were designed to establish hydrogen bonding between hydroxyl and carboxyl with that of UV/c-Al2O3 composites at the same filler content. It was found that the addition of 0.5 wt % h-Al2O3 increases the AC breakdown strength and volume resistivity by 15.5 % and 367.9 %, respectively. Our results suggest that the hydroxylation is an efficient way to improve the electrical properties of UV-cured resin nanocomposites, thus promoting stereolithography 3D printing in application of electrical and electronic field.
关键词： Stereolithography,Interfacial region,Hydrogen bonding,Nanocomposites,Interfacial strength,Trap levels,Electrical properties
更新于2025-09-23 15:19:57
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Graphene Based THz Electromagnetic Imaging System for the Analysis of Artworks
摘要： In this paper, a graphene-based electromagnetic imaging system working in 140–220 GHz frequency band for nonintrusive analysis of 3D artwork is presented. A single-stage high-order frequency multiplier is used to generate the signal at the transmitter module, whereas the single-stage high-order subharmonic mixer acts as a signal detector at the receiver. Both modules exploit the nonlinear response of graphene sheets excited by an incident electromagnetic wave, to generate harmonic components and mixing products of the input signals, respectively. The transmitter and the receiver modules were implemented through an additive manufacturing process. The resulting electromagnetic imaging system prototype was applied to the analysis of ceramic vessels, showing its ability to detect enclosed objects and to obtain information in cross-sectional planes. Furthermore, the geometrical parameters and filling material characterization can be obtained by processing the frequency response of the scattered field.
关键词： graphene,submillimeter wave devices,stereolithography,Frequency multiplier,subharmonic mixer
更新于2025-09-19 17:15:36
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Effect of attenuate light on polymerization of ceramic suspensions for stereolithography
摘要： Weak bonding strength between interlayers can seriously affect the quality of ceramic parts manufactured by stereolithography. Therefore, the possibility of using chemical bonds to strengthen the adhesion within these parts and the extent to which may be effective are of interest. Thus, a multi-exposure model was built to illustrate the state of this interface. The secondary conversion of a cured layer defined as conversion rate increment caused by decayed ultraviolet (UV) light in a subsequent exposure was selected to represent the extent of a chemical bond. The level of UV light attenuation occurred when travelling through a suspension layer was determined using the Attenuation Law. When decayed light illuminated a cured layer, it underwent further photopolymerization, which was detected by temperature change. The secondary conversion was affected by parameters including the incident energy dose and the propagating length. Optimization of these parameters helped to achieve higher chemical bond ratio.
关键词： Ceramic stereolithography,Secondary photopolymerization,Multi-exposure model,Light attenuation
更新于2025-09-19 17:15:36
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Investigation of Inverse Solutions for Tilting Orthogonal Double Prisms in Laser Pointing with Submicroradian Precision
摘要： This paper reports the design, fabrication, and characterization of arrays of miniaturized, internally fed, polymer electrospray emitters fabricated with stereolithography. The freeform additive manufacturing process used to make the devices has associated two orders of magnitude reduction in the fabrication cost per device and fabrication time (from thousands of dollars to tens of dollars, and from months to hours, respectively) and a two orders of magnitude reduction in the cost of the manufacturing infrastructure (from millions of dollars to tens of thousands of dollars) compared with a silicon MEMS multiplexed electrospray source. The 3-D printed devices include features not easily attainable with other microfabrication methods, e.g., tapered channels and threaded holes. Through the optimization of the fabrication process 10-mm tall, isolated, straight, solid columns with diameter as small as 300 μm, and 12-mm long, straight tubes with inner diameter as small as 400 μm and wall thickness as small as 150 μm were demonstrated. Arrays with as many as 236 internally fed electrospray emitters (236 emitters in 1 cm2) were made, i.e., a twofold increase in emitter density and a sixfold increase in array size compared with the best reported values from multiplexed, internally fed, electrospray sources made of polymer. The characterization of devices with a different array size suggests a uniform emitter operation.
关键词： electrospray,Additive manufacturing of MEMS,stereolithography,multiplexed liquid ionizers
更新于2025-09-19 17:13:59
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A 3-D Printed E-Plane Waveguide Magic-T Using Air-Filled Coax-to-Waveguide Transitions
摘要： This article reports on a new class of broadband and fully 3-D printed E-plane coax-to-waveguide transition and a monolithically 3-D printed waveguide magic-T based on the transition. The transition is constructed by a section of air-filled rectangular coaxial transmission line (TL) that is placed between two broadband coax-to-waveguide probe transitions. It is used to interconnect the magic-T’s sum port and the waveguide T-junction. The incorporation of the transition reorients all the waveguide arms of the magic-T into the E-plane. Some X-band prototypes of the proposed transition and the magic-T are designed and implemented. Polymer-based additive manufacturing and copper electroplating techniques are employed to monolithically fabricate each prototype. The transition and the magic-T exhibit broadband and low-loss characteristics from 8.2 to 12.4 GHz with the measured performance well matched with the simulations. In addition, the power handling capability (PHC), including the peak PHC (PPHC) and the average PHC (APHC), of the magic-T is evaluated by simulations, showing that the proposed magic-T could handle 100 W of APHC.
关键词： E-plane waveguide magic-T,stereolithography apparatus (SLA),air-filled coaxial transmission line (TL),Additive manufacturing,coax-to-waveguide transition
更新于2025-09-16 10:30:52
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Cross-Coupled Repetitive Control of a Compliant Nanomanipulator for Micro-Stereolithography
摘要： This paper proposes an easy-implemented and high precision contouring control method for a self-developed compliant nanomanipulator supporting cost-effective micro-stereolithography (MSL). The proposed contouring control method is composed of a repetitive controller (RC) to achieve periodic trajectory tracking for each axis, and a cross-coupled control (CCC) for the coordination of contour errors. It is worth noting that the cross-coupled controller design and its integration to RC are not straightforward, as an incorrect feedback position may even deteriorate the contouring and an inappropriate design of the cross-coupled controller leads to instability of the system. For the proposed control structure, a correct feedback position is designed, hence a cross-coupled controller is constructed to ensure the stability and contour error reduction. Various simulations and real-time experiments are deployed on the nanomanipulator, and the comparative results validate the enhanced contour tracking performance of the proposed control method with the contour error 86 nm.
关键词： Contouring control,mechatronics,micro-stereolithography,tracking,nano-positioning
更新于2025-09-16 10:30:52
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[IEEE 2019 17th International Conference on ICT and Knowledge Engineering (ICT&KE) - Bangkok, Thailand (2019.11.20-2019.11.22)] 2019 17th International Conference on ICT and Knowledge Engineering (ICT&KE) - Provision and Visualization of Solar Radiation Data for Energy Management System
摘要： This paper reports the design, fabrication, and characterization of arrays of miniaturized, internally fed, polymer electrospray emitters fabricated with stereolithography. The freeform additive manufacturing process used to make the devices has associated two orders of magnitude reduction in the fabrication cost per device and fabrication time (from thousands of dollars to tens of dollars, and from months to hours, respectively) and a two orders of magnitude reduction in the cost of the manufacturing infrastructure (from millions of dollars to tens of thousands of dollars) compared with a silicon MEMS multiplexed electrospray source. The 3-D printed devices include features not easily attainable with other microfabrication methods, e.g., tapered channels and threaded holes. Through the optimization of the fabrication process 10-mm tall, isolated, straight, solid columns with diameter as small as 300 μm, and 12-mm long, straight tubes with inner diameter as small as 400 μm and wall thickness as small as 150 μm were demonstrated. Arrays with as many as 236 internally fed electrospray emitters (236 emitters in 1 cm2) were made, i.e., a twofold increase in emitter density and a sixfold increase in array size compared with the best reported values from multiplexed, internally fed, electrospray sources made of polymer. The characterization of devices with a different array size suggests a uniform emitter operation.
关键词： electrospray,Additive manufacturing of MEMS,stereolithography,multiplexed liquid ionizers
更新于2025-09-16 10:30:52
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3D Printing Temporary Crown and Bridge by Temperature Controlled Mask Image Projection Stereolithography
摘要： Traditionally, the fabrication of temporary teeth restorations must go through multiple processes such as moulding, curing and post finishing, which requires extensive expertise of dentists. In addition, the handmade temporary restorations are usually unable to precisely fit the patient’s teeth due to limited formability of material. To address the problem, a three-dimensional (3D) printing technology named temperature controlled mask image projection based stereolithography (TCMIP-SL) is presented for dental materials in this paper, with aim to build customized temporary crown and bridge quickly for its use in dental offices. We first studied the photo-polymerization performance of commercial materials that are commonly used in dental industry. Then we discussed the temperature effect on curing performance and rheology of dental composite material. Based on the studies, we further developed our TCMIP-SL process by integrating a material coating system with controllable heating, so that the coated thin film of dental composite material can be selectively cured using high resolution patterned light beam. Several test cases are performed to demonstrate the TCMIP-SL process can 3D print high viscous temporary crown material with fast speed and high resolution.
关键词： Continuous material film coating,Stereolithography,Temporary crown and bridge,High viscosity,Additive manufacturing
更新于2025-09-12 10:27:22
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[IEEE 2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems & Eurosensors XXXIII (TRANSDUCERS & EUROSENSORS XXXIII) - Berlin, Germany (2019.6.23-2019.6.27)] 2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems & Eurosensors XXXIII (TRANSDUCERS & EUROSENSORS XXXIII) - Out-of-Plane Long-Range Operated Soft Engine with Driving Stretchable Zone Plate and Led Abilities for Tunable Focused Therapeutic Ultrasonic and Infrared Heating Applications
摘要： This paper presents a soft engine which performs the long-range up-and-down motion with four planar film-structured electroactive polymer (EAP) actuators. The engine can dynamically tune the focus of ultrasonic beam by driving the foil-made stretchable Fresnel zone plate with out-of-plane motion. Moreover, the micromachined buckles and serpentine structure were utilized to convert the bending motion of a pair of actuators to the linear motion along with lighting up the light-emitting diode (LED). We successfully demonstrate that the developed device stretches the zone plate to tune the focal point of the ultrasonic beam up to 4 mm. Also, controlling the LED to turn on and off in a moving cycle of the soft engine is displayed.
关键词： stereolithography,Electroactive polymer,actuators,zone plate,ionic polymer metal composite
更新于2025-09-11 14:15:04
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[ASME ASME 2018 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference - Quebec City, Quebec, Canada (Sunday 26 August 2018)] Volume 1B: 38th Computers and Information in Engineering Conference - Predicting Manufactured Shapes of a Projection Micro-Stereolithography Process via Convolutional Encoder-Decoder Networks
摘要： Projection micro-stereolithography (P-μSLA) processes have been widely utilized in three-dimensional (3D) digital fabrication. However, various uncertainties of a photopolymerization process often deteriorates the geometric accuracy of fabrication results. A predictive model that maps input shapes to actual outcomes in real-time would be immensely beneficial for designers and process engineers, permitting rapid design exploration through inexpensive trials-and-errors, such that optimal design parameters as well as optimal shape modification plan could be identified with only minimal waste of time, material, and labor. However, no computational model has ever succeeded in predicting such geometric inaccuracies to a reasonable precision. In this regard, we propose a novel idea of predicting output shapes from input projection patterns of a P-μSLA process via deep neural networks. To this end, a convolutional encoder-decoder network is proposed in this paper. The network takes a projection image as the input and returns a predicted shape after fabrication as the output. Cross-validation analyses showed the root-mean-square-error (RMSE) of 10.72 μm in average, indicating noticeable performance of the proposed convolutional encoder-decoder network.
关键词： P-μSLA,convolutional encoder-decoder network,Projection micro-stereolithography,shape deformation prediction,deep neural networks
更新于2025-09-10 09:29:36