- 标题
- 摘要
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- 实验方案
- 产品
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Cellulose nanopaper with controllable optical haze and high efficiency ultraviolet blocking for flexible optoelectronics
摘要： For Zn-nanopapers obtained from grafting of Zn(II)-terpyridine complex (Zn-tpy) into tCNFs (2,2,6,6-tetramethylpiperidine-1-oxyl radical, TEMPO, oxidized cellulose nano?brils), their optical hazes were ?rst found to be highly dependent on alcohol-characteristic solvent stimulation. By addressing the controllable issue of benzyl alcohol (BA) disposal, the optical haze of Zn-nanopaper was adjusted to regulate from BA-induced instability wrinkling and swelling patterns, which was dictated by Zn-nanopaper thickness. Moreover, upon long-term UV radiation, these Zn-nanopapers exhibited stable UV-blocking, which, together with the optical haze adjustment, offered an opportunity for utilization in ?uorescent lamps, ?at panel displays or glass walls.
关键词： Oxidized cellulose nano?brils,Post-processing,Controllable optical haze,Zn(II)-terpyridine,UV-blocking
更新于2025-09-23 15:22:29
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Laser polishing of 3D printed metallic components: A review on surface integrity
摘要： 3D Printing is an emerging technology to fabricate complex components in less lead time compared to traditional manufacturing processes. 3D printing enables to build metallic functional components directly from CAD model by depositing the material layer by layer. The fabricated components generally have very rough surfaces and demands for post processing, so that it can directly employ for its end use. Owing to drawbacks like time consuming, skilled labour requirement and limited scope of automation, conventional ?nishing processes ?nd less application for ?nishing freeform components. Laser Polishing is a highly productive, contactless and fully automatic post processing technique which is giving promising results to lower the surface roughness of 3D printed metallic components from the past two decades. In laser polishing, when the components are irradiated by the laser radiation, peaks of the surface are melted to a very thin layer and redistributed into the valleys by surface tension and gravity. Laser polishing has shown its ability to polishing varieties of materials from re?ective materials like aluminium to high strength materials like Inconel and Titanium alloys. In this present article, a review of laser interaction on surface integrity and mechanical properties of different materials used in metallic 3D printing are reported. The optimum process parameters of laser polishing like laser power, beam diameter, scanning speed and scan spacing/step over are also mentioned with respect to each material.
关键词： Post processing,Surface roughness,Finishing,Metallic additive manufacturing,Selective laser melting,Laser re-melting
更新于2025-09-23 15:19:57
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Post-Processing of FDM 3D-Printed Polylactic Acid Parts by Laser Beam Cutting
摘要： In this paper, the post-processing of 3D-printed poly lactic acid (PLA) parts is investigated. Workpieces are manufactured by fused deposition modeling (FDM) 3D printing, while they may have defects in some areas such as edges. A post-processing is introduced here for 3D-printed samples by low power CO2 laser. The thickness of the FDM samples are 3.2 mm and printed by optimum conditions. Effects of process parameters such as focal plane position (?3.2–3.2 mm), laser power (20–40 W), and laser cutting speed (1–13 mm/s) are examined based on the design of experiments (DOE). Geometrical features of the kerf; top and bottom kerf; taper; ratio of top to the bottom kerf are considered as output responses. An analysis of the experimental results by statistical software is conducted to survey the effects of process parameters and to obtain regression equations. By optimizing of the laser cutting process; an appropriate kerf quality is obtained and also optimum input parameters are suggested. Experimental verification tests show a good agreement between empirical results and statistical predictions. The best optimum sample with 1.19 mm/s cutting speed, 36.49 W power and 0.53 mm focal plane position shows excellent physical features after the laser cutting process when 276.9 μm top and 261.5 μm bottom kerf width is cut by laser.
关键词： fused deposition modeling,laser cutting,3D printing,additive manufacturing,post-processing,design of experiments
更新于2025-09-19 17:13:59
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In-Process Laser Re-Melting of Thin Walled Parts to Improve Surface Quality after Laser Metal Deposition
摘要： Laser metal deposition (LMD) is an additive manufacturing process highly adaptable to medium to large sized components with bulky structures as well as thin walls. Low surface quality of as-deposited LMD manufactured components with average roughness values (Ra) around 15-20μm is one of the main drawbacks that prevent the use of the part without the implementation of costly and time-consuming post-processes. In this work laser re-melting is applied right after LMD process with the use of the same equipment used for the deposition to treat AISI 316L thin walled parts. The surface quality improvement is assessed through the measurement of both areal surface roughness Sa(0.8mm) and waviness Wa(0.8mm) parameters. Moreover, roughness power spectrum is used to point out the presence of principal periodical components both in the as-deposited and in the re-melted surfaces. Then, the transfer function is calculated to better understand the effects of laser re-melting on the topography evolution, measuring the changes of individual components contributing to the surface roughness such as the layering technique and the presence of sintered particles. Experiments showed that while low energy density inputs are not capable to properly modify the additive surface topography, excessive energy inputs impose a strong periodical component with wavelength equal to the laser scan spacing and directionality determined by the used strategy. When a proper amount of energy density input is used, laser re-melting is capable to generate smooth isotropic topographies without visible periodical surface structures.
关键词： laser metal deposition,direct energy deposition,Additive manufacturing,post-processing,surface roughness,laser re-melting
更新于2025-09-16 10:30:52
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Post-processing of additively manufactured cutting edges by laser ablation
摘要： In the packaging industry, cutting dies are used to process paper based material. The dies are mainly manufactured via steel strip principle, which consists of many manual steps and is difficult to automate. Laser material processing represents a promising approach to simplify manufacturing. This study realized additively manufactured cutting edges post-processed by laser ablation to achieve a defined final profile shape. First verification shows that laser ablation appears to be attractive for finishing of additively manufactured cutting edges.
关键词： angle of incidence,additive manufacturing,hybrid production,laser ablation,cutting edge,post-processing
更新于2025-09-12 10:27:22
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Laser surface texturing of titanium with thermal post-processing for improved wettability properties
摘要： The use of lasers to create microstructures on metal surfaces in order to change the wettability properties a material has been widely explored, mainly using ultra-short pulsed lasers working in the femto and picosecond regime. In order to explore a more robust industrial method for the creation of super-hydrophobic surfaces, a fibre based nanosecond pulsed laser has been used to process polished Ti6Al4V samples to produce customised topography. The samples then received a low temperature annealing post-treatment. This, decrease the time needed for reaching the super-hydrophobic point considerably. The nanosecond pulsed laser provides a thermal component in the surface, helping with the creation of micro pillars in the surface morphology. The use of scanning electron microscopy (SEM) with energy dispersive X-Ray analysis (EDX), white light optical profiling, and contact angle measurements were used to characterize and quantify the effects of the surface modification on the wetting properties of the material.
关键词： laser surface texturing.,superhydrophobic,Nanosecond laser,thermal post-processing
更新于2025-09-12 10:27:22
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Direct Machining of selective laser melted components with optimized support structures
摘要： Selective laser melting (SLM), as a rapidly growing additive manufacturing technology, is used to produce complex components with integrated functionalities. Nevertheless, limited part properties like surface roughness or geometrical accuracy impede their direct use right after printing. Therefore, functional surfaces have to be post-processed (e.g. milling, grinding, polishing), which significantly raises the product costs. To increase the process efficiency, direct post-processing without part removal from the build platform is presented. For this, geometrical accuracy was investigated and cutting forces were measured to investigate their influence on the stability of the support structures to allow precise machining and an increased productivity.
关键词： direct machining,additive manufacturing,post-processing,support structures,selective laser melting
更新于2025-09-12 10:27:22
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Laser surface modification and polishing of additive manufactured metallic parts
摘要： The combination of additive manufacturing (AM) and subsequent laser polishing is a technical approach with high flexibility in comparison to conventional processes. AM parts often present the need of post-processing due to surfaces with roughness higher than the admissible for most applications. The laser polishing consists in ablation and melting of a small amount of material, through laser irradiation, which is redistributed to create a surface with low roughness and probably new functionalities. Besides the flexibility, laser polishing presents high processing speed and capability for localized surface treatment. In this study, the resulting characteristics of AM parts irradiated by laser sources with different technical features are investigated and discussed. The parameters applied were the pulse duration, scan speed, repetition rate and average laser power. To evaluate the impact of laser processing on the material the microstructure and surface roughness were analysed and correlated to the process parameters.
关键词： post-processing,Additive manufacturing,laser polishing,surface modification
更新于2025-09-12 10:27:22
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Laser-based imaging applications in turbid waters
摘要： Underwater laser-based imaging systems and data-processing techniques matured during the past decade. Active imaging systems can, nowadays, be integrated into platforms like remote-operated vehicles (ROV) or autonomous underwater vehicles (AUV). This article gives an overview of different civil and naval applications in underwater imaging with respect to underwater laser scanning (ULS) and laser gated viewing (LGV). Special emphasis has to be given to the environmental conditions, for example, the influence of the local and seasonal dependence of the turbidity with regard to the optical underwater channel. On the basis of tank and sea experiments, advanced techniques for 3D laser oblique scanning (LOS) and possibilities of contrast enhancements for gated viewing are presented.
关键词： laser scanner,laser gated viewing,underwater laser imaging,post-processing
更新于2025-09-11 14:15:04
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Implementation of Real-Time Post-Processing for High-Quality Stereo Vision
摘要： We propose a novel post-processing algorithm and architecture that simultaneously uses the passive and active stereo vision information to improve the reliability of the three-dimensional disparity in a hybrid stereo vision system. The proposed architecture consists of four steps — left-right consistency checking, semi-2D hole filling, a tiny adaptive variance checking, and a 2D weighted median filter. The experimental results show that the error rate of the proposed algorithm (5.77%) is less than that of a raw disparity (10.12%) for a real-world camera image having a 1,280 × 720 resolution and maximum disparity of 256. Moreover, for the famous Middlebury stereo image sets, the proposed algorithm’s error rate (8.30%) is also less than that of the raw disparity (13.7%). The proposed architecture is implemented on a single commercial field-programmable gate array using only 13.01% of slice resources, which achieves a rate of 60 fps for 1,280 × 720 stereo images with a disparity range of 256.
关键词： post processing,hole filling,variance check,FPGA,weighted median filter,Stereo vision,3D depth
更新于2025-09-10 09:29:36