Aluminum matrix composites reinforced with boron carbide are currently employed in the nuclear industry. It's used as a control rod in nuclear reactors; Since B4C has very high absorption cross section for thermal neutrons. The objective of this work is to study the effect of heat treatment on the mechanical properties of the Al–B4C metal matrix composites prepared by powder metallurgy techniques. Compressibility was measured with the Al powder. The chosen compaction pressure was 2500psi. Samples were prepared by adding 5%, 10%wt B4C to Al as well as the Al powder. Sinterability was evaluated at different temperatures (400,450,500,550,600,650°C) during 2, 4, 6, 8; 10 hr for soaking time. Mechanical test were evaluated, showed little improvement in hardness, compressive strength and young's modulus in temperatures 400,450,500,550°C, and significant improvement in hardness and compressive strength in temperatures 600and 650°C, and also improvement to the elastic modulus. Specific samples were irradiated by neutron source, and mechanical tests showed little decrease in their mechanical properties (hardness and compressive strength) due to low neutron fluence available that gives insignificant effect.