Abstract
A small amount of Ag, Bi, Cd, Co, Cr, Fe, Mo, Ni, Pb, Sb, Sn, Ti, W and Zn has been added singly to the duralumin(Cu 4%, Mg 0.5%, Mn 0.5% rest Al), and the effect of these elements on the grain-refinement of the slabs, on the age-hardening and on the mechanical properties of the duralumin has been investigated. The results obtained maybe summarised as follows:
(1) The addition of Co, Cr, Fe, Mo, Ti and W was found to be effective for the grain-refinement of the slabs.
(2) By the addition of Ag, Co, Cr, Fe, Mo, Ni, Pb, Ti and W, the age-hardening of the duralu-min was retarded.
(3) The mechanical properties of the duralumin were improved by the addition of Cd, Co, Cr (<0 6% ), Mo (<0.5%), Pb, W (<0.3%) and Zn, but the addition of Ag, Bi, Fe, Ni, Sb, Sn and Ti gave no effect.
