Influence of metal-ceramic interfaces on the behaviour of metal matrix composites and their joints

摘要

The present contribution emphasises the importance of the chemical reactions which occur during the fabrication and joining procedures, in the metallic matrix/ceramic reinforcement interfaces of the metal matrix composites. Using both theexperimental data obtained by other investigators studding metal/ceramic systems such us Al/SiC, Al-Mg/Al{sub}2O{sub}3, Ti/SiC, etc.; and the results of the research carried out for the present authors in the diffusion bonding of Al/SiC andAl-Mg/Al{sub}2O{sub}3 composites, the nature of these chemical reactions and their influence on the MMC properties are discussed.Authors also study the particularly case of the participation of Li in the interface reactions occurred in the Al/SiC system, For it, the data obtained in the study of the diffusion bonding of an aluminium-copper alloy (AA2124) reinforced with SiCwhiskers and using an aluminium-lithium alloy (AA8090) as interlayer, are used. TEM observations showed that Li might change the nature of this interface and penetrate in the SiC lattice. It can answer to the increase in interface strength detected byother authors in Al-Li/SiC composites. The application of TEM has proved to be an essential tool for characterisation of these kind of interfaces.