Manufacturing of functionally graded metal matrix composite materials by segregation
|Autoren:||Behrens, B.-A.; Bohr, D.|
|Veröffentlichung:||International Journal of Materials Research (formerly Zeitschrift für Metallkunde) 109(5), pp 373–380.|
By applying vibrations to a granular media differing in size and density, various segregation states can be established. If an additional rotational motion is engaged, the effective force is no longer gravity but a centrifugal one, leading to a radial segregation. In this contribution, an experimental setup is presented which utilizes these effects. This setup is used to produce a cylindrical metal matrix composite consisting of silicon carbide and aluminium having a radial gradient. The influence of different material- and processspecific parameters on the segregation behaviour was investigated. The evaluation of micrographs of the pressed and sintered samples shows that both positive and negative gradients can be achieved. The rotation speed and the grain size ratio were identified as significant factors. The variation of the vibration amplitude leads to opposite effects. On the one hand, the gradient intensity increased. On the other hand, the variances of the SiC distribution in the tangential or radial directions increased as well. In addition, it has been shown that the effects of different grain shapes are marginal.