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Grand Falls-Windsor, Canada

Villafuerte J.,CenterLine Windsor Ltd. | Wright D.,Accuwright Industries
Advanced Materials and Processes | Year: 2010

A thermal spray shop in Arizona has taken the industry lead to qualify cold spray as an adequate repair methodology for high value aircraft components made of aluminum and/or magnesium alloys, including gear box housings, inlet housings, and aircraft actuators. The shop uses commercially available low-pressure cold spray equipment to perform mechanical and corrosion repairs of these components following FAA-approved procedures. The components are then machined to required dimensional specifications. After machining, protective finishes, primers, and top coats can be successfully applied to the required areas. After basic surface preparation, the corroded area can be successfully restored using cold spray. Cold spray can produce high quality thick metallic deposits of pure metals, alloys, and composites having extra low oxide content and negligible or no porosity. Source

Villafuerte J.,CenterLine Windsor Ltd. | Wright D.,Accuwright Industries
Welding Journal (Miami, Fla) | Year: 2010

Cold spray constitutes a family of emerging solid-state processes that expand the capabilities of traditional thermal spraying into unique applications that are either technically or economically prohibitive for traditional thermal spray. Cold spray can produce high-quality, ultrathick metallic deposits of specially formulated metal powders with low oxide content and porosity. Low-pressure cold spraying has become a reliable, accurate, and economical technique for the manufacturing or refurbishing of rotatable sputtering targets for high-volume thin-film deposition. Source

Villafuerte J.,CenterLine Windsor Ltd.
Advanced Materials and Processes | Year: 2014

Cold spray is beneficial in applications that use heat-sensitive substrate materials or those with difficult-to-reach spray areas. One example involves spraying inside small-diameter, heat-sensitive tubes or bores to provide corrosion resistance. Cold spray produces deposits that are oxide-free and fully dense with acceptable mechanical properties. The process requires heating of a pressurized carrier gas that is passed through a 'DeLaval' convergent-divergent nozzle. The divergent section of the nozzle creates a supersonic gas jet as the carrier gas expands toward the nozzle exit. The spray material is injected into the gas jet either upstream or downstream of the nozzle throat. Each material requires a specific minimum particle velocity to successfully form a well bonded and dense deposit, depending on the process temperature. Source

Villafuerte J.,CenterLine Windsor Ltd.
Metal Finishing | Year: 2010

Cold spray is a coating process that uses a high-speed gas jet to accelerate powder particles toward a substrate. Some of the characteristics of cold spray include the ability to form dense deposits with extremely low oxygen content, free of residual tensile stresses, grain growth, recrystallization zones, and phase changes. In low-pressure cold spray, air or nitrogen at relatively low pressure is also preheated, and then forced through a DeLaval nozzle. At the nozzle, the expansion of the gas produces the conversion of enthalpy into kinetic energy, which accelerates the gas flow to supersonic regime while reducing its temperature. Cold spray technology falls under the larger family of thermal spray processes, and it is not here to replace any of the well-established thermal spray methods. Because of its low-temperature deposition, cold spray can be used to embed micro-sensors, along with functional coatings, on surfaces for smart structures. Source

Berube G.,University of Ottawa | Yandouzi M.,University of Ottawa | Zuniga A.,University of Chile | Ajdelsztajn L.,University of Ottawa | And 2 more authors.
Journal of Thermal Spray Technology | Year: 2012

In this study, aluminum alloy Al-5Fe-V-Si (in wt.%) feedstock powder, produced by rapid solidification (RS) using the gas atomization process, was selected to produce high-temperature resistant Al-alloy coatings using the cold gas dynamic spraying process (CGDS). The alloy composition was chosen for its mechanical properties at elevated temperature for potential applications in internal-combustion (IC) engines. The CGDS spray process was selected due to its relatively low operating temperature, thus preventing significant heating of the particles during spraying and as such allowing the original phases of the feedstock powder to be preserved within the coatings. The microstructure and phases stability was investigated by means of Scanning Electron Microscopy, transmission electron microscopy, X-ray diffraction and differential scanning calorimetery techniques. The coatings mechanical properties were evaluated through bond strength and microhardness testing. The study revealed the conservation of the complex microstructure of the rapid solidified powder during the spray process. Four distinct microstructures were observed as well as two different phases, namely a Al 13(Fe,V) 3Si silicide phase and a metastable (Al,Si) x(Fe,V) Micro-quasicrystalline Icosahedral (MI) phase. Aging of the coating samples was performed and confirmed that the phase transformation of the metastable phases and coarsening of the nanosized precipitates will occurs at around 400 °C. The metastable MI phase was determined to be thermally stable up to 390 °C, after which a phase transformation to silicide starts to occur. © ASM International. Source

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