Metal matrix composite
Metal matrix composites (engl. Metal matrix composite , MMC ) consist of a continuous metal matrix having a discontinuous ceramic or organic reinforcement in its interior, often in the form of fibers or whiskers . So-called preform MMCs, in which both phases are continuous, are often referred to as MMCs. One of the first applications was in the Space Shuttle program around 1975. This was a very light (approx. 1.8–3.5 g / cm³), difficult to machine material with good thermal conductivity and low thermal expansion. Other properties can also be set in a targeted manner in accordance with the requirements during manufacture.
MMC is usually made of reinforced aluminum or titanium , in special cases also reinforced magnesium and copper materials . The matrix is in the form of an elemental metal or in the form of an alloy . Ceramic particles (e.g. silicon carbide ), short fibers, continuous fibers (based on carbon) or foams with open porosity are used as the reinforcement phase.
There are several manufacturing processes for metal matrix composites:
- Stirring ceramic particles into the molten metal
- Powder metallurgy
- Welding stacks of foils with fibers
- electrical deposition
- diecast
- Infiltration of (ceramic) preforms using die casting or casting presses
- Spray deposition
- Reactions in which one product is the matrix and the other is the reinforcement
- PVD
- directional solidification
MMC are used commercially in power electronics, the automotive industry ( brake drums , drive shafts , cylinder liners ), the railroad (brake drums), in aviation and as cutting tools.
See also
Web links
- Metal matrix composite materials Custom-made materials (accessed on August 6, 2020)
- Metal Matrix Composits (MMCs) (accessed August 6, 2020)
- Production and characterization of a SiC / Cu metal matrix composite material with adapted fiber / matrix interface (accessed on August 6, 2020)
- Composite materials with multi-metal matrix A new opportunity for MMCs? (accessed on August 6, 2020)
- Process for the production of a metal matrix nanocomposite material, metal matrix nanocomposite material and its application (accessed on August 6, 2020)