Effect of Artificial Aging on Plane Anisotropy of 6063 Aluminium Alloy

Most aluminum profiles’ production by deep-drawing and extrusion processes require certain degree of structural homogeneity because of the segregated second-phase particles in the as-cast structure. Rolled texture and directionality in properties often give rise to excessive earring, breakout, and tears. This study investigates the effect of heat treatment (artificial aging) on the anisotropic behavior of AA6063 alloy between rolling direction (0°) through 90° directions. The results show significant reduction in property variability in the aged samples along the rolling direction 0°, and 90° directions compared with the as-cast samples. This gave rise to improved % elongation, impact toughness, and substantial reduction (33.3%) in hardness. These results are capable of achieving huge savings in die conditioning and replacement with improved quality and sale of deep-drawn AA6063 alloy profiles for sustained profitability. 1. Introduction In metal forming, texture gradients often ensued due to nonhomogeneous flow. Texture heterogeneities can also occur in other deformation modes, such as sheet rolling, wire drawing and tube extrusion. Thus, in many industrial forming processes for aluminum, mechanical loading is usually combined with some form of heat treatment such as annealing between deformation steps. This serves the purpose of mitigating substantially strain-hardening phenomenon during deformation. A particular example is the stretching of aluminum parts in a number of stages with intermediate annealing treatments. However, this heating and cooling cycle often results in time wastage and could be minimized. The cause of work hardening during mechanical working varies in different aluminium alloy compositions. Hardening of nonheat treatable Al-Mg alloys is due mainly to the presence of solute atoms in solid solution. In heat treatable Al-Mg-Si and Al-Cu alloys, strengthening is determined by precipitates formed during aging treatment. For room-temperature forming, the material behaviour of aluminum sheet is completely determined by work hardening and almost independent of the strain rate [1]. Previous study showed that profiles extruded from both homogenized and unhomogenized billets did exhibit the same mechanical properties and metallurgical features [2]. Hence, the whole homogenizing process could be eliminated without compromising any of the mechanical properties. It is established that the factors that determine behaviour of aluminium alloy component are the type, amount, and distribution of second-phase particles such as Al-Fe, Al- Fe-Si, and