Metal matrix composite

Metal matrix composites (English metal matrix composite, MMC ) are of a continuous metal matrix having a discontinuous ceramic or organic reinforcement in its interior, frequently. Into the form of fibers or whiskers Also so-called preform MMCs, in which both phases are continuous, are often referred to as MMC. One of the first applications was the use of the Space Shuttle program about 1975. It was a very light (about 1.8-3.5 g / cc), are difficult to cut material with good thermal conductivity and low thermal expansion. Other properties can be set according to the requirements specifically in the production.

In MMC, there are usually reinforced aluminum or titanium, in special cases, to increased magnesium and copper materials. The matrix is present as elemental metal or as an alloy. As the reinforcing phase are ceramic particles (e.g., silicon carbide ), chopped strands, continuous fibers ( carbon- based ), or foams for use with open porosity.

There are several manufacturing processes of metal matrix composite materials:

  • Stirring ceramic particles in the metal melt
  • Powder Metallurgy
  • Welding of film stacks with fibers
  • Electrodeposition
  • Die-cast
  • Infiltration of ( ceramic ) preforms by pressure casting or Giesspressen
  • Sprühdeposition
  • Reactions in which the product constituting the matrix and the other the reinforcement
  • PVD
  • Directional solidification

Commercially come MMC in the automotive industry ( brake drums, drive shafts, cylinder liners ), Rail ( drums ), in aviation and as cutting tools used.

Aluminium Cermet
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