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Advances and Applications of Nontraditional Machining Practices for Metals and Composite Materials
Published in T. S. Srivatsan, T. S. Sudarshan, K. Manigandan, Manufacturing Techniques for Materials, 2018
Ramanathan Arunachalam, Rajasekaran Thanigaivelan, Sivasrinivasu Devadula
In the ultrasonic machining process, the ultrasonic vibration of the tool horn and abrasive slurry plays a prominent role in material removal. A new ultrasonic machining method using ultrasonic complex vibration caused by the longitudinal and torsional vibration was proposed by Asami and Miura (2015a) to improve the machining speed and the machining accuracy. A new fabrication method to achieve precision hole machining through sacrificing the coating on the substrate is proposed by Baek et al. (2013). In this method, a hard wax is deposited on the glass substrate, and holes are precisely fabricated in the coated glass using ultrasonic machining. Last, a wax coating is removed by cleaning. The presence of wax coating protects the surface of the glass by accepting the cracks rather than on the surface. Hence, the surface cracks and roundness error of the machined holes are generated in the sacrificed coating attributes to improve the performance of ultrasonic machining. For machining a deeper cavity, a new method known as ultrasonic vibration filing is considered for inner surface machining of a deep-cavity component made of carbon fiber–reinforced silicon carbide composites. The carbon fiber with ultrasonic vibration creates high-frequency scratching at short times. These small fragments produced from scratching detach the big block of material and improve surface integrity and surface quality (Wang et al. 2016b). Other important factors such as tool vibrating amplitude, tool material (stainless steel, silver steel, nimonic), and tool profile (solid and hollow tool) also play a significant role in improving the output parameters.
Value Added and Waste Elimination
Published in John Nicholas, Lean Production for Competitive Advantage, 2018
A process may itself contain steps that are ineffective or unnecessary. Take, for example, a product that goes through two steps: cutting, then filing to remove burrs along the cut edge (Figure 3.4a). This process might be altered to reduce wasted time and steps. Automatic filing of the edge is more efficient than manual filing (Figure 3.4b); still better is periodic maintenance or replacement of the cutting tool so it gives a smooth edge that does not need filing (Figure 3.4c). The item might even be redesigned so the cutting operation is eliminated (Figure 3.4d).
Hand and power tools
Published in Andrew Livesey, Alan Robinson, The Repair of Vehicle Bodies, 2018
Pneumatic sander/filer. This is a dual-purpose tool for either sanding or filing. For sanding, an abrasive paper sheet is clipped to the tool. It has a reciprocating straight-line action which speeds up feather edging or filing materials and results in a smooth surface finish. A standard file blade can be fitted to the tool’s base to convert it into a power-operated body file with a speed of up to 3000 strokes per minute.
Impact of rheological model on numerical simulation of low-pressure powder injection moulding
Published in Powder Metallurgy, 2021
Raphaël Côté, Mohamed Azzouni, Oussema Ghanmi, Sarthak Kapoor, Vincent Demers
More recently, the Moldflow Synergy package was used to optimise the injection parameters of ceramic-based low-viscosity feedstocks, including for controlling the temperature [14], the filing time [15], the pressure [16] and the jetting phenomenon [17]. However, this software only allows to introduce the average powders radius and the volume fraction of powder contained in the feedstock. Therefore, the selection of the rheological constitutive equation is critical since rheological characteristics such as viscosity, shear thinning sensitivity and yield stress are directly influenced by the powder distribution and morphology [18]. Although the potential to predict the flow behaviour of HPIM and LPIM feedstocks has been demonstrated, the influence of the rheological constitutive equations used to describe metallic-based LPIM feedstocks in simulation results has not been clearly established in the literature. Therefore, the aim of this study is to investigate the impact of a rheological model on the simulated mouldability of metallic-based LPIM feedstocks.
Post-processing treatments to enhance additively manufactured polymeric parts: a review
Published in Virtual and Physical Prototyping, 2021
F. Tamburrino, S. Barone, A. Paoli, A. V. Razionale
VBF and BF, though similar, are characterised by certain differences. VBF tends to produce smoother surfaces because the abrasive action occurs at each vibration pulse, resembling a filing process. In BF, higher cutting forces are exerted because the parts tumble against each other, rather than gently rubbing together, and thus it is suitable for tougher materials. However, VBF machines are usually more complex and expensive than BF systems.
Performance comparison of sensible and latent heat-based thermal storage system during discharging – an experimental study
Published in Experimental Heat Transfer, 2022
In order to evaluate the performance of the TES system in real-time scenario, an experimental test rig has been designed and fabricated at the Indian Institute of Technology Roorkee, India. Figures 1 and 2 presents a schematic of the TES system and a pictorial view of an experimental setup for this study. The TES system comprised of solar energy simulator, centrifugal blower and storage tank. To supply thermal energy to the storage tank, a solar energy simulator made of Ni-chrome wire has been fabricated having an area of 1525 mm × 310 mm. A 3-phase, 3 kW centrifugal blower with 2880 rpm is used for driving the air through the storage tank module. The storage tank is cylindrical in shape, made of mild steel having an outer diameter of 40 mm and 1.2 m height. The height of packed bed in the tank is kept as 0.7 m. The storage tank is insulated with glass wool and polyethylene foam for reducing the heat loss from the TES tank. The schematic of the interior of the cylindrical storage tank and the position of thermocouples in the storage tank are shown in Figures 3 and 4. The storage tank has air distributors at the top and bottom edges of the storage tank to ensure the uniform distribution of air through the packed-bed system. The storage tank is filled with 1600 concrete spheres having a dimeter of 38 mm in sensible TES and 1600 paraffin encapsulated metallic capsules with a dimeter of 38 mm in latent TES as shown in Figure 5 (a) and (b). Paraffin encapsulation was performed by filing a liquid PCM into 95% of total volume of stainless steel spheres to eliminate the thermal expansion in the capsules during melting. A porosity of 0.4 is achieved by packing the concrete and encapsulated spheres in a random manner for both the storage configurations. Air has been selected as a HTF for the experimentation, which can reduce the cost of the system. The properties of concrete and paraffin storage materials are presented in Table 1.