It is not possible to describe the quality of the materials the Mn-modified and base alloys was calculate dusing the following expression [46,47].where: UTS is the ultimate tensile strength, M is the materials constant and E is the percentage of elongation. Here, M¼150 was considered for both alloys as adopted from [47].
As seen in Table3, the calculated quality index, Qindex, for the Mn modified alloy in the T6 heat-treated condition is higher than that for the Mn-modified alloy in the as-cast state and the base alloy in the T6 heat treated condition. It is seen that the modified alloy in the as-cast and T6 heat-treated conditions obtained the Qindex value of 363 and 525 MPa respectively,while the base alloy in the same T6 state reached a Qindex of 418MPa. Thus,it can be concluded that the alloy modified with additions of Mn in the T6 state has better tensile properties than the base alloy and commercial alloys A380 and A319.