Elucidating the Effect of TiB2 Volume Percentage on the Mechanical Properties and Corrosion Behavior of Al5083-TiB2 Composites

Abstract

Al5083-TiB2 in situ composites with 1, 3, and 5 volume percentages of TiB2 were fabricated. The effect of different volume percentages of TiB2 reinforcement particles on the mechanical properties and corrosion resistance of these composites was investigated. The hot extrusion process resulted in fragmentation and more homogeneous distribution of TiB2 particles throughout the Al5083 matrix. Also, the grain size reduced as the amount of TiB2 reinforcement particles increased which caused the improvement of both the strength and ductility of the material. It was shown that the hardness, the ultimate tensile strength (UTS), and the yield strength (YS) of both the as-cast and extruded materials increased with increasing TiB2 content. Also, TiB2 addition combined with the extrusion process improved both UTS and elongation (El.%) of the extruded structures which can be attributed to the presence of TiB2 particles and obtained microstructural refinement by hot extrusion process. However, the extruded Al5083-5 vol.% TiB2 composite showed lower ductility in comparison with the extruded Al5083-1 vol.% TiB2 and Al5083-3 vol.% TiB2 composites. Moreover, it could be concluded that the corrosion resistance and also the pitting corrosion behavior of the Al5083 alloy do not significantly change in the presence of TiB2 reinforcement particles.