Executive Summary : | The demand of electric vehicles (EV) is increasing significantly in India as well as globally for reducing the dependency on crude oils & reducing the vehicular pollution, to promotes green technologies, and various schemes/subsidies/incentives supported by the governments further increased its popularity [1-5]. It is generalized that by reducing the 100 kg weight of the electric vehicles will increase the cost of EV up to 10 % to 15 % [6]. The aluminum alloys are the preferred choice by the EV manufacturer [7], because they are lighter, cheaper and easily available [8]. Tesla and other companies are using aluminium alloys for making battery casing, and body frame of electric vehicles [9], but most of the automotive industries using Al-Mg-Si alloys for producing the parts of the EV [10]. The aluminium is highly recyclable and 75 % of the aluminium ever produced is still in used today [11]. It saved around 99.40 GJ/t of extra energy required for production of primary aluminium [12]. In the proposed work, high specific strength Al-Mg-Si alloys will be developed for producing the body frame of EV by: (i) Adding new chemical elements, (ii) Thermo-mechanical processing. (i) Effect of chemical composition: The addition of each element (Indium, Sn, Scandium, Cu, Cd, Zn, and Cu) separately into the Al-Mg-Si alloys significantly influencing the age hardening response of developed Al alloys [13-19]. The peak hardness obtained during the ageing treatments, depend upon the wt % of new elements added, and ratio of Mg/Si [14, 17, 20]. The Ag and Cu addition into Al-Mg-Si alloys improved the age-hardening kinetics during the ageing treatment [21]. The alone Ag-addition into Al-Mg-Si alloys promotes the age hardening by formation of Mg-Ag phase, and Q' phase (Mg9Si7Ag2Al3) [22]. The detrimental effect of natural ageing ahead of the paint baking can be removed by adding the Ag, Cu and Indium into the Al-Mg-Si alloys [13, 21, 22]. It can be inferred that addition of appropriate elements into Al-Mg-Si alloys not only accelerate the ageing kinetics, even eliminate the detrimental effect of natural ageing of Al-Mg-Si alloys. (ii) Effect of thermo-mechanical processing: The pre-ageing immediately after the solution treatment, and ahead of paint baking steep significantly improve the mechanical properties of AA6061 Al alloy by increasing the number density of Mg-Si co-clusters, and by decreasing the density of single species Si-Si and Mg-Mg clusters [23]. The ageing after the solution treatment followed by asymmetric rolling, and then again ageing of the Al-Mg-Si alloy improved the mechanical properties [24]. The forming processes such as forging, ECAP, Rolling, Hybrid process, etc., in combination with the ageing treatment improved the monotonic and dynamic strength of Al-Mg-Si alloys [25-39]. It can be inferred that designing of noble thermo-mechanical processes have a potential scope for further improving the mechanical properties of Al-Mg-Si alloys. |