Metal matrix composites disadvantages

One disadvantage is that metal matrix composites have to be processed at markedly larger temperature. This not only increases the requirements on tools used during processing, but also on the fibres which have to withstand... 

Purely inorganic sol-gel silica coatings have also been used for mechanical protection of metals [51,54,55] and metal matrix composites [5,16,56]. The main disadvantage of purely inorganic vitreous Si02 coatings is their brittleness [33], and the use of multilayered systems is usually adopted. 

Metal particles may be embedded in a polymer matrix in a variety of ways. These are chemical synthesis in an organic solvent [2], vacuum deposition on viscous-flow polymers [3], plasma polymerization combined with metal evaporation [4], and so on. However, they all suffer from disadvantages, such as a low filling factor or a great spread in size and shape of particles synthesized, which offsets the good optical properties of composites. 

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