Investigation of effective parameters on graphite distribution in FGM structure of A۳۵۶/Al۲O۳/Gr composite

In this research, aluminum/alumina/graphite hybrid composite was prepared by horizontal centrifugal casting method, and the microstructure and distribution of alumina and graphite particles in the radial direction of the cross-sectional area of the samples were investigated. The distribution of graphite and alumina particles has led to the creation of a gradual structure (FGM) along the cross section. As a result of the centrifugal force, the graphite particles separated in the inner part of the sample and the alumina particles gradually increased from the inner region to the outer region. The samples were obtained with ۳, ۵ and ۷% by volume of graphite particles added to the melt and with the rotation speed of the mold RPM۱۰۰۰, RPM۱۵۰۰ and RPM۲۰۰۰, and the formation of the inner zone rich in graphite was investigated. In all samples, ۳% by volume of alumina particles were used and the effect of the presence of alumina particles on the distribution of graphite particles was studied. Optical microscope (OM) was used to investigate the microstructure and distribution of graphite and alumina particles. By increasing the amount of graphite from ۳ to ۷ percent by volume, the collision and interaction between graphite particles increases and leads to an increase in the thickness of the inner layer rich in graphite, and increasing the speed of rotation of the mold first causes an increase in the thickness of the inner layer and then leads to It was reduced. The presence of alumina particles prevented the complete separation of graphite particles

کلیدواژه ها:

Aluminum matrix composite ، FGM structure ، centrifugal casting ، Hybrid composite ، graphite and alumina