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Factors Effecting the Demand for Electricity From the Smart Grid
Published in Clark W. Gellings, Smart Grid Planning and Implementation, 2020
There are a number of new technologies on the horizon that are not included in the EPRI analysis (ORNL 2012). These include the following:Electron beam melting, which enables precision melting of powder materials and processing of complex geometries not possible through machining.Ultrasonic additive manufacturing, which enables a simultaneous additive and subtractive process for manufacturing complex geometries. In addition, a solid-state process allows embedding of optical fibers and sensors.Laser metal deposition, which allows site-specific material addition; application of advanced coating materials for corrosion and wear resistance; and the repair of dies, punches, turbines, etc.Fused deposition modeling, which is the precision deposition of thermoplastic materials and the development of high-strength composite materials for industrial applications. It also enables transformation of rapid prototyping to rapid manufacturing.High-velocity laser accelerated deposition (HVLAD), which is a new photonic method for producing protective coatings with ultra-high-strength, explosively bonded interfaces. These coatings prevent corrosion, wear, and other modes of degradation in extreme environments. In addition to being crucial to future fusion reactors, HVLAD materials and coatings have other important uses including bearing and shafts for wind turbines, corrosion-resistant structures of offshore platforms, better pipelines for oil and gas transmission, and ultra-hard corrosion-resistant surfaces for naval ships (R&D 100 2011).Ultraviolet LED (UV LED) can be applied to industrial curing. This technology offers energy savings compared to mercury lamps as well as to the use of gas to air dry conventional coatings. Energy savings of more than 60% have been reported. The technology radiates ultraviolet light and uses it to cure ultraviolet-sensitive coatings. UV light impacts the photo-initiators in the coating which become excited, passing energy along to other particles in the coating. This stimulates a bonding process between molecules. Excited components, called free radicals, maintain the reaction.
Assessment of nanoparticle emission in additive manufacturing: Comparing wire and powder laser metal deposition processes
Published in Journal of Occupational and Environmental Hygiene, 2023
Roberta Pernetti, Simone Maffia, Barbara Previtali, Enrico Oddone
Among AM innovative variants, laser metal deposition (LMD) processes can adopt different metal alloys as feedstock and powders or wire as matrices (Ahn 2021). Powder LMD has been extensively studied because its predecessor is the laser cladding process, which has been in widespread industrial use since the 1960s. However, LMD processes utilizing wire as a feedstock are a more recent innovation that owes their success to new coaxial deposition heads, which improved the efficiency of the process (Li et al. 2022). The advantages of using wire as a feedstock include high deposition rates, ease of storage, zero material waste, lower material costs, and fewer safety hazards (e.g., elimination of handling of combustible dust) associated with the use of metal powders. Because the use of metal wire feedstock eliminates risks associated with the handling of combustible dust and potential exposure to powders, exposure hazards associated with the use of metal wire may often be unforeseen. Although previous studies have demonstrated the release of NPs in powder LMD processes (Bau et al. 2020), there is limited evidence of NP generation when using metal wire as an LMD feedstock. This study aims to provide preliminary data for comparing NP release during the powder and wire LMD processes and to propose considerations for including NP safety in risk management protocols for LMD operators.
Laser metal deposition characterization study of metal additive manufacturing repair of rail steel specimens
Published in Virtual and Physical Prototyping, 2023
Alagu Subramaniam Nellian, John Hock Lye Pang
Advances in metal additive manufacturing processes have been made in powder blown Laser Metal Deposition (LMD) methods for metal additive manufacturing repair applications. Robot-assisted LMD process provides a practical solution for metal deposition repair and remanufacturing of worn or damaged steel parts for high value industrial components like turbine blades, oil and gas drill shafts, and automotive engine parts (Sexton et al. 2002; Shepeleva et al. 2000; Siddiqui and Dubey 2021; Torims 2013; Zhu et al. 2021). The deposition of clad material alloy in the form of powder offers a diverse material selection range, relatively low dilution rates, and precise deposition that is suitable for most industrial applications. Laser is used as the energy source to direct heat input across the metal substrate surface to be repaired. The heat input then creates a melt pool layer on the metal substrate surface while powder material from a coaxial powder nozzle head is deposited concurrently onto the melt pool and fused with the substrate forming a single-track layer. Subsequent deposition of overlapping layers allows a build-up of metal repaired surfaces, layer-by-layer with the laser metal deposition process (Toyserkani, Khajepour, and Corbin 2004).
Nonlinear thermal simulation of laser metal deposition
Published in Australian Journal of Mechanical Engineering, 2021
Diego Montoya-Zapata, Juan M. Rodríguez, Aitor Moreno, Oscar Ruiz-Salguero, Jorge Posada
Laser Metal Deposition (LMD) is an additive manufacturing process in which metal powder is delivered on top of a substrate while a laser melts the added material to produce a new layer. LMD has gained importance during the last several years because of its applications in the repair, coating and manufacturing of high-valued industrial parts (Leino, Pekkarinen, and Soukka 2016).