Cymat Technologies
| |
Public Corporation | |
Industry | |
Founded | 1995 |
Headquarters | Mississauga, Ontario, Canada |
Products | Aluminum foam |
Website | http://www.cymat.com/ |
Cymat Technologies is a public corporation based out of Mississauga, Ontario, Canada, and one of the world leaders[1] in the production of Aluminum foam.
Process
As described in the patent originally created by Alcan[2] 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;[2]
- 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.[3] It is thought that particulate aids in foam stability via the following mechanisms:
- Slows the flow of molten metal through the cell walls to help maintain a stable structure.
- A repulsive force which helps to maintain the cell wall thickness between two adjacent cells.
- 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.[7] 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.[8] While it is drawn off, it is then cooled and forms a porous metallic structure.
See also
External links
References
- ↑ Cymat Technologies
- 1 2 Patent US4973358
- 1 2 3 M. Mukherjee, Evolution of Metal Foams during Solidification, Page 20, October 14, 2008
- 1 2 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
- ↑ C. Korner, Foam Formation Mechanisms in Particle Suspensions applied to Metal Foams, September 28, 2007
- ↑ Manufacturing Routes for Metallic Foams
- ↑ Method of producing lightweight foamed metal