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Go to Editorial ManagerSpecimens with the structure of a face-centered cubic were produced using several sets of printing conditions. An experimental testing is conducted to carefully evaluate the microstructural analysis and compressive strength of this structure. The results include the measurement of mechanical properties, such as the peak stress. Fused deposition modeling is employed for the additive manufacturing of experimental specimens made from shape memory polymer thermoplastic polyurethane (MM-3520). We take into account the impact of printing factors on lattice structures, such as layer thickness, printing temperature, and printing speed. Analyzing the microstructure of the printed specimens exhibits that the specimens with highest printing temperature, lowest printing speed and thinner printing layer have better layers adhesion and lower porosities. All the mechanical tests are performed on specimens with the same structure and at a relatively constant density. Among the tested printing parameters, using a layer height of 0.1 mm, a printing temperature of 230 °C, and a printing speed of 20 mm/s yields the highest strength in the specimens. However, specimens printed with a layer height of 0.2 mm, a printing temperature of 220 °C, and a printing speed of 30 mm/s also exhibit good strength, albeit slightly lower than the maximum values. Additionally, when using these specific settings (0.3 mm – 210 °C – 40 mm/s), the mechanical qualities are minimized, yet the stress-strain curves exhibit characteristics similar to elastomers.
Over the last several years, additive manufacturing (AM), sometimes known as "3D printing", has seen remarkable expansion due to mechatronics and materials science advancements. Fused filament deposition (FDM) production is the predominant technology in additive manufacturing (AM) because of its cost-effectiveness in operational and material expenses. Nevertheless, the materials often used for this technique are pristine thermoplastics. Unsuccessful printing and throwaway prototypes generate a significant quantity of trash. Utilizing green and sustainable products is crucial to minimize the environmental effects. Recycled, bio-based, and mixed recycled materials provide a promising solution for 3D printing. The absence of comprehension about the interlayer adhesion process and material degradation in FDM printing has presented a significant obstacle for these environmentally friendly materials. This study comprehensively examines many materials used for FDM three-dimensional printing filaments, including recycled, bio-based, and mixed materials. The merits and drawbacks of thermoplastics and their composites were deliberated over. This evaluation is a comprehensive guide for engineers and researchers in selecting appropriate materials for three-dimensional printing. Three-dimensional printed objects have worse mechanical characteristics in comparison to injection molded materials.
Fused deposition modeling (FDM) is a commonly used 3D printing technique that involves heating, extruding, and depositing thermoplastic polymer filaments. The quality of FDM components is greatly influenced by the chosen processing settings. In this study, the Taguchi technique and artificial neural network were employed to predict the ultimate tensile strength of FDM components and establish a mathematical model. The mechanical properties of ABS were analyzed by varying parameters such as layer thickness, printing speed, direction angle, number of parameters, and nozzle temperature at five different levels. FDM 3D printers were used to fabricate samples for testing, following the ASTM-D638 standards, using the Taguchi orthogonal array experimental design method to set the process parameters. The results indicated that the printing process factors had a significant impact on tensile strength, with test values ranging from 31 to 38 MPa. The neural network achieved a maximum error of 5.518% when predicting tensile strength values, while the analytical model exhibited an error of 19.376%.
In the field of engineering, 3D printers are indispensable due to their high precision. This study focuses on the construction and optimization of a 3D printer using aluminum T-slotted bars for the frame, Raspberry Pi 4 for control, and Lightburn software for image printing and machine control. After assembling the main components and programming with Marlin firmware, the machine was tested for vibration and noise reduction. The research compared the vibration of a diode laser and spindle during printing, revealing significantly lower vibration with the laser compared to the spindle. These findings demonstrate the effectiveness of the constructed 3D printer in reducing vibration and noise during operation.
Prosthetic is an artificial tool that replaces part of the human frame absent because of ailment, damage, or distortion. The current activities in Iraq draw interest to the upper limb discipline because of the growth in variety of amputees and. It is necessary to do extensive researches in this subject to help lessen the struggling of patients. This paper describes the design and development of low-cost prosthesis for people with transradial amputations. The presented design involves a hand with five fingers moving by means of a gear box mechanism. The design of this artificial hand allows five degrees of freedom(5DOF), one degree of freedom for each finger. The artificial hand works by an actuation system (6V) Polou motor with gear ratio equal to 50:1 due to its compactness and cheapness. The designed hand was manufactured by a 3D printing process using polylacticacid material (PLA). Some experimental were accomplished using the designed hand for gripping objects. Initially the EMG signal was recorded when the muscle contracted in one second, two seconds, three seconds. The synthetic hand was able to produce range of gesture and grasping moves separately just like the actual hand by using KNN classification which are complete hand Pinch, fist, and jack chuck. The simulation of the fingers movements was achieved using ANSYS software to analysis the movement (pinch, fist, and jack chuck), obtain bested of stress influencer at each finger, and maximum deformation at each movement.
Laser annealing represents a powerful method for tailoring the properties of silver nanofilms on quartz substrates, offering advantages in terms of precision, scalability, and functionalization. Continued research efforts are expected to deepen our understanding and broaden the applications of this promising technology in diverse fields. In this work, laser annealing of silver nanofilms deposited on quartz substrates was performed and investigated. RF CO2 laser of variable power in the range 1–20 W with beam quality of 1.1 was used to anneal silver nanofilms. AFM analysis emphasized that nanocrystal sizes of 60 nm were obtained for silver nanofilms. Furthermore, the optimum absorbance peak occurred at about 449 nm for smaller film thickness. Thermal simulation and analysis of the annealing process were also conducted using COMSOL Multiphysics software. It was observed that optimal temperature of 729 K was achieved when 10 W laser power and 2 mm/s scanning speed were used to anneal 20 nm silver film thickness. Design of expert analysis was also used to better understand the laser annealing process of silver nanofilms since convolution of several process parameters affect the process output.