Heat treatment process consists of a series of operations that include heating at a specific rate, soaking at a specific level for a long of time, and cooling at a specific rate. The primary goal of this research is to analyse how heat treatment affects the microstructure and mechanical properties of aluminium alloys 6101. The selected quenching media (spent engine oil, coconut juice, air cool, and sugar cane juice) were hence selected as they have been known to increase the general mechanical properties of aluminium alloy 6101. The impact and hardness properties of the heat-treated samples were studied, and their microstructural characterizations were obtained. It was established that from the results obtained and their discussions, impact strength increases as the annealing temperature increases, while hardness of the samples reduced with increase in annealing temperature. Air cooled has a higher impact strength than sugar cane juice cool, while sugar cane juice cool outperformed engine oil medium, and engine oil medium outperformed coconut juice medium.