The aim of this study is investigation of the effect of sintering temperature and hot cross rolling process on physical, mechanical and microstructural properties of Al-30 wt. % (B4C) composite fabricated by hot pressing process. Powders of Aluminum with 20 μm and B4C with 45 μm particle size were milled by planetary mill machine for 4 h with 200 rpm. Then mixed powder was sintered by hot pressing machine at 550, 600, and 650 °C for 1 h under 50 Mpa in a vacuum. Then samples were preheated at 500 °C for 20 min and hot cross rolled in 8 passes (25 % reduction). For characterization of the samples, density of the samples by Archimedes method, microhardness, XRD, and FESEM analysis were performed. The results showed the density and hardness of hot pressed samples were increased from 2.29 to 2.51 g/cm3, and 90.56 to 127.33 Vickers, respectively. Also, after hot cross rolling, the density and hardness of the samples were increased from 2.35 to 2.64 g/cm3, and 90.56 to 127.33 Vickers, respectively. X ray patterns showed inter phases such as AlB31 form during hot pressing process. Also, performing of hot cross rolling process can lead to decrease the size of B4C particles and uniform distribution in Aluminum matrix. The best sintering temperature at 650 OC and performing 25 % hot cross rolling process lead to have a composite with the highest density and lowest porosity and water absorption.
