Role of hot-rolling and heat-treatment of in-situ chemical reaction of Al7075/Gr./TiB2 hybrid composite in microstructure, grain size and yield strength

This paper discovers the effect of hot rolling and heat-treatment on Al7075/Gr./TiB 2 hybrid composite fabricated through in-situ chemical reaction process. The prepared cast specimens have been machined to a size of 45 × 50 × 11 mm and specimen was heated to 400℃ for 1 hr. duration in an electric furnace. Further, heated specimen has been hot-rolled and 80 % reduction was achieved. Thereafter, microstructure test samples and tensile test samples were machined as per ASTM-E3 and ASTM-A370 standard test size. It is observed that, on polished surface higher weight percentage of graphite particles, cluster formation and uniform dispersion are noticed before rolling. However, after hot-rolling the clustering was scarcely seen which is related to strain-rate induced during hot-rolling process, size of graphite particle and its weight percentage. Grain size for hot-rolled Al7075/8 % Gr./5 %TiB 2 exhibits reduction of 36 % when assisted with Al7075 alloy alone. However, yield strength exhibits improvement of 58 %.