Functionally graded materials produced by friction stir processing

An investigation was conducted in order to produce aluminium based functionally graded MMC reinforced by SiC ceramic particles with median size of 118.8, 37.4 and 12.3 μm. AA5083 aluminium alloy plates in the H111 and partially annealed conditions were processed. Several strategies for reinforcement were investigated and its influence on the particle distribution and homogeneity was studied. A square shaped groove packed with reinforcement particles of SiC was studied and it was seen that it was more effective when the groove was placed under the probe. If the groove was placed outside the probe interaction area, but within the shoulder influence area, insufficient dispersion of particles was observed. Small particles lead to higher concentration along the bead surface and to smooth fraction gradients both in depth and along the direction parallel to the surface. The thickness of the reinforced layer depends of particle size within the parametric conditions and the tool geometry used in this investigation.