Effect Of Zinc Addition on the Microstructure and Mechanical Properties of 6063 Aluminum Alloy

This research work entails addition of Zinc metal to the 6063 aluminium alloy series. The Zinc addition ranged from a percentage of 1% - 5% at an interval of 0.5%. Charge calculations were made and the aluminium alloy and Zinc were melted in a crucible furnace. Permanent mold casting was utilized with dimension of 150 mm * 15 mm. The 6063 aluminium – Zinc alloy was machined to standard tensile dimensions of G.D 5 mm, G.L 40 mm, external diameter 8 mm, two opposite external length of 30 mm; hardness dimensions of 20 mm * 20 mm * 20 mm; and impact dimensions of length 60 mm, diameter 10 mm, notch at 30mm with 3mm depth. The aluminium- zinc alloys were heat treated to 300 oC and 400 oC; and held at a soaking time of 2 hours, allowed to cool in the furnace and another series of aluminium - zinc alloy was not heat treated.
The specimens were destructively tested and the homogenized 400 oC aluminium-zinc alloy possessed the greatest strength of 237 MPa, a hardness value of 113 HV, a maximum percentage elongation of 22.5% and a maximum impact energy of 70.5 J. Thus, the alloy can be used for applications requiring high strength and hardness coupled with low ductility.