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Cymat Technologies is a Canadian Public Corporation based out of Mississauga, Ontario, and one of the world leaders〔(Cymat Technologies )〕 in the production of Aluminum foam. == Process == As described in the patent originally created by Alcan〔(Patent US4973358 )〕 with parallel patents created by Norsk Hydro, “Stabilized Aluminum Foam” is generated in a continuous casting process via direct shop air injection into a Metal Matrix Composite (MMC) melt. The MMC comprises an Al-Si cast alloy with a volume of particle in suspension. The purpose of the particle is to provide melt stability and must adhere to the following criteria; * Consist of Alumina, Titanium diboride, Zirconia, Silicon Carbide, Silicon nitride or any solid stabilizer materials * Must compose of less than 25 vol% of the MMC * Particulate sizes must range from 0.5 μm – 25 μm, preferably in the range of 1 μm to 20 μm Though it is a controversial topic, it is widely accepted that the presence of the solid particles aid in the "stabilization" of bubbles.〔M. Mukherjee, ''Evolution of Metal Foams during Solidification'', Page 20, October 14 2008〕 It is thought that particulate aids in foam stability via the following mechanisms: * Increase bulk liquid viscosity〔M. Mukherjee, ''Evolution of Metal Foams during Solidification'', Page 20, October 14 2008〕〔S.W. IP, Y. Wang and J.M. Toguri, ''Aluminum Foam Stabilization by Solid Particles'', Page 2, March 30 1998〕〔W. Deqing and S. Ziyuan, ''Effect of Ceramic Particles on Cell Size and Wall Thickness of Aluminum Foam'', May 15 2003〕 :: *Slows the flow of molten metal through the cell walls to help maintain a stable structure. * Creates a mechanical disjoining pressure〔M. Mukherjee, ''Evolution of Metal Foams during Solidification'', Page 20, October 14 2008〕〔C. Korner, ''Foam Formation Mechanisms in Particle Suspensions applied to Metal Foams'', September 28 2007〕 :: *A repulsive force which helps to maintain the cell wall thickness between two adjacent cells. * Reduction in Drainage〔S.W. IP, Y. Wang and J.M. Toguri, ''Aluminum Foam Stabilization by Solid Particles'', Page 2, March 30 1998〕 :: *Presence of particulate in the foam helps to impede the flow of molten metal in the direction of gravity by obstructing the cell walls and sustaining the liquid. The process for the creation of Stabilized Aluminum Foam and can be broken down into these 4 rudimentary steps: #Melting #Air Injection #Casting #Solidification Once the raw MMC is melted, it is then transferred to the foaming apparatus where gas is injected into the melt and dispersed using either rotating impellers or vibrating nozzles.〔(Manufacturing Routes for Metallic Foams )〕 The bubbles rise to the surface and the resultant metal foam mixture cast will rise out of the foaming apparatus due to its density relative to that of the molten MMC. As the metallic foam is being cast, it is simultaneously drawn off the surface by, for example, a conveyor belt.〔(Method of producing lightweight foamed metal )〕 While it is drawn off, it is then cooled and forms a porous metallic structure. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Cymat Technologies」の詳細全文を読む スポンサード リンク
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