Effect of double thermal ageing treatment on the mechanical properties of Al–Cu–Mg/3% rice husk ash composite

The effect of double thermal ageing treatment (DTAT) on the hardness, impact and tensile properties of Al–Cu–Mg/rice husk ash composite produced by double stir casting method has been studied. From the results obtained, DTAT samples showed better hardness, impact and tensile properties as compared with the STAT samples. These significant improvements were evidenced in the DTAT for 5 h (with a hardness value of 81.3 HRB) and DTAT for 4 h with impact strength of 72 kJ/m2 and Ultimate tensile strength of 129.797 N/mm2 respectively. The Microstructural analysis revealed that more precipitates were formed and more evenly distributed in the DTAT than STAT. It can be deduced that the thermal treatment has improved the mechanical properties of the composite studied under this condition.