Surface engineering and surface-engineered materials are increasingly used in engineering. This study's major goal is to understand the effects of heat treatment on AA 6061-T6. This experiment uses many parameters such as heat treatment temperature, steel heat treatment duration at the same temperature and cooling medium. In this experiment an attempt to improve the result for the mechanical properties and electrical conductivity values at different levels to use the technique which is called Taguchi method and ranking algorithm. Through this study aims to do optimization of various process parameters. To get the precise results used as a standard ASTM A370-E8 method to find out the response of the treated samples in the L<inf>9</inf> orthogonal experimental design. During the experiments, nine samples of AA6061-T6 and all the nine pieces quenched at three different temperature pre-aging temperature of 300, 350 and 400°C, pre-aging time of 1, 2 and 3 hours, re-aging temperature of 350, 400 and 450 °C and quenching medium of water/air/oil. The model implemented this with TOPSIS-Technique of Order Preference Similarity to the Ideal Solution by Taguchi method and to conclusion that the optimum parameters for better response like pre-aging temperature of 350 °C, pre-aging time of 1 hr., re-aging temp. of 350 °C and quenching medium of water. The current study found distinct characteristics for mechanical and electrical conductivity in heat treatment ageing. © 2024 Elsevier B.V., All rights reserved.