Experimental Investigation of Mechanical Properties in Al-Si Alloy with varying Magnesium Content

Energy efficiency is one of the major considerations for any automobile, be it an IC engine powered vehicle, an electric vehicle or a solar powered vehicle. Materials used for the construction of a vehicle directly affect energy efficiency, as weight decides energy consumption. There is an ever-growing need for new, light-weight materials, alloy compositions which offer better strength-to-weight ratio and mechanical properties, without compromising on safety and cost of production. Lightweight materials without loss of strength, is the present and the future of the automotive manufacturing industry. Among the lightweight materials that are considered for use in automobiles like aluminum, magnesium, titanium, carbon fiber, other composite materials, Aluminum has attained global attention and attracted automotive and aerospace engineers by virtue of the range of material properties. These material properties offer huge applications in various engineering verticals. Automotive body manufacturing using aluminium has reached mass production, for many popular models. Numerous automotive chassis components, wheels and battery enclosures for EV's/HEV's are produced using aluminium rather than steel, because of its light weight, high strength and anti-corrosive properties. However, the fight against the weight of the car/automobiles will continue, and it will be a new level in connection with the strictness of efficiency and environmental requirements. Considering the above need, this research is done to study Al-Si alloy mechanical properties-Al-20Mg-4Si-2Cu-2Mn (specimen 01), Al- 30Mg-4Si-2Cu-2Mn (specimen 02), Al-40Mg-4Si-2Cu-2Mn (specimen 03), by variation of weight percentage of magnesium by 1%. The fundamental aim of this research is to know the importance of Mg concentration in Al-Si alloy by checking the mechanical properties, depending on the results of mechanical properties obtained, study the suitability of the alloy for automotive applications. Specimen 2 showed the highest ultimate tensile strength (96.52 N/mm2), representing a 15.0% and 3.6% increase over specimens 1 and 3, respectively, along with superior yield strength (77.77 N/mm2)-an 86.2% and 5.5% improvement. The hardness was maximum for specimen 3 (75 HBW), showing 8.7% and 1.3% gains compared to specimens 1 and 2. In contrast, compressive strength was highest in specimen 1 (425 N/mm2), exceeding specimens 2 and 3 by 18.3% and 26.6%, while impact strength remained constant at 0.04 J/mm2 across all specimens. Major Findings: Specimen 2 showed improved mechanical properties (tensile, yield strength, hardness) compared to all specimens, whereas compression strength got improved in specimen 1.