Fused filament fabrication (FFF) is a popular additive manufacturing (AM) method for creating thermoplastic parts with intricate geometrical designs. Pure thermoplastic materials utilized in FFF, whose polymeric matri...
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Fused filament fabrication (FFF) is a popular additive manufacturing (AM) method for creating thermoplastic parts with intricate geometrical designs. Pure thermoplastic materials utilized in FFF, whose polymeric matrix is reinforced with other materials, such as carbon fibers (CFs), introduce products with advanced mechanical properties. However, since not all of these materials are biodegradable, the need for recycling and reuse immediately emerges to address the significant problem of how to dispose of their waste. The proposed study evaluates the printability, surface morphology and in vitro toxicity of two thermoplastic-based composite materials commonly used in wearable device manufacturing to provide enhanced properties and functionalities, making them suitable for various applications in the field of wearable devices. Tritan Copolyester TX1501 with 7.3% chopped CFs (cCFs) and Polyamide 12 (PA12) with 8.6%cCFs and 7.5% iron Magnetic Nanoparticles (MNPs)-Fe4O3 were used in the discrete ascending cycles of recycling, focusing on the surface quality performance optimization of the printed parts. Through stereoscopy evaluation, under-extrusion, and over-extrusion defects, as well as non-uniform material flow, are assessed in order to first investigate the influence of various processparameters' application on the printing quality of each material and, second, to analyze the optimal value fluctuation of the printing parameters throughout the recycling cycles of the materials. The results indicate that after applying certain adjustments to the main printing parameter values, the examined recycled reinforced materials are still effectively 3D printed even after multiple cycles of recycling. A morphology examination using scanning electron microscope (SEM) revealed surface alterations, while a cytotoxicity assessment revealed the adverse effects of both materials in the form of cell viability and the release of proinflammatory cytokines in the cell culture medium.
Nowadays, to reduce the cost of coal liquefaction and to produce a new liquid fuel alternative to petroleum, it is considered a more convenient method to liquefy coal and biomass together instead of solely coal liquef...
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Nowadays, to reduce the cost of coal liquefaction and to produce a new liquid fuel alternative to petroleum, it is considered a more convenient method to liquefy coal and biomass together instead of solely coal liquefaction. Liquefaction experiments were carried out by changing the solvent/solid ratio of 1/1-5/1, reaction temperature 320-400 degrees C, reaction time 30-90 min, and algae/lignite ratio in the range of 1/1-5/1. As a result of this study, the most suitable processparameters obtained by considering total conversion are;solvent/solid ratio 3/1, reaction time 60 min, algae/lignite ratio 4/1, and reaction temperature 380 degrees C. Under these conditions, the highest total conversion is approximately 80% and 77% in catalytic and non-catalytic conditions, respectively. Under non-catalytic conditions of co-liquefaction experiments due to the GC-MS results, cyclopentane (raw material of motor oil), pentadecane, 2-methyl-naphthalene, octa-ethylene glycol, ethylene oxide heptamer are the main products of optimum parameters aforementioned for oil. They are mainly used in fuel technology and used in the chemical industry as raw materials mean low-cost production as well.
In this paper, DOE method is applied to scheme test plans for designing the casting processes with shrinkage volume information provided by InteCAST. The effect on casting defect by the setting of riser style, riser s...
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ISBN:
(纸本)9783037855591
In this paper, DOE method is applied to scheme test plans for designing the casting processes with shrinkage volume information provided by InteCAST. The effect on casting defect by the setting of riser style, riser section, riser height, chill section, chill thickness was studied by the range analysis and the influences degree of above five factors were compared by the variance analysis. The trend graphs of factor level are drawn to intuitively present the degree of importance of the factor. Optimal processparameters are obtained by using comprehensive analysis and comprehensive score method. A practical exemplification is shown to prove that the proposed method could help designer efficiently obtain an optimal feeding layout.
In this thesis, a series of typical planar gas-assisted injection molding parts are created. With the help of CAE software moldflow, the GAIM process of these parts are simulated and the analysis results are received....
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In this thesis, a series of typical planar gas-assisted injection molding parts are created. With the help of CAE software moldflow, the GAIM process of these parts are simulated and the analysis results are received. By the thorough study and mathematic treatment of the results, a set of rules between gas parameters and gas penetration length are concluded, furthermore, three formulas of gas parameters and gas penetration length are deduced. At the end, three verifying models are created to validate the formulas.
Based on the test analyses of grinding surface layer behavior of spiral bevel gears, many conclusions are gottenCompressive residual stresses are occurred on grinding tooth surface, tensile residual stresses are locat...
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ISBN:
(纸本)9783038351023
Based on the test analyses of grinding surface layer behavior of spiral bevel gears, many conclusions are gottenCompressive residual stresses are occurred on grinding tooth surface, tensile residual stresses are located in tooth layer, and change laws of grinding residual stresses are different from ones of grinding surface roughness Ra as the grinding processparametersA temper layer is occurred in tooth layer after normal grinding, and the micro-hardness of grinding surface is lowerWhen arriving at the critical condition, namely grinding temperature is above 600 degree Celsius, and metamorphic layer depth is greater than 0.2mm, different degree of grinding burn is produced, and their microstructures are changedBased on grinding orthogonal test L16(45), the optimizing configuration of grinding processparameters of spiral bevel gear is obtained by using a mean variance analysis of integrated balance methodBased on the test optimization of grinding surface layer behavior, the comprehensive performances of grinding surface, such as grinding residual stresses, surface roughness, micro-hardness and structure, metamorphic layer depth et al, are betterThese provide a basis for improvement of grinding surface quality of spiral bevel gears.
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