The solidification of undercooled melts via twinned dendritic growth

The solidification of undercooled Cu–x wt.% Sn (x=1, 2, 3, 4) alloys has been studied by a melt encasement (fluxing) technique. It was found that below undercoolings of ΔT≈90 K the preferred dendrite growth orientation in each of these alloys was along the 〈1 1 1〉 direction. Moreover the 2 and 3 wt.% Sn alloys also displayed evidence of twinned growth. Above ΔT≈90 K the preferred growth direction returned to the more usual 〈1 0 0〉 orientation.