Stress induced deformation in the solidification of undercooled Co₈₀Pd₂₀ alloys

Substantial undercooling ΔT up to 415K was achieved for Co₈₀Pd₂₀ melt applying molten glass denucleation combined with cyclic superheating. The as-solidified structure as function of ΔT was described concisely. On this basis, dense-regular fault (DRF) ribbons were detected provided if a critical undercooling is surpassed. An integrated analysis of the DRF formation with a model calculation [16] for shrinkage-stress developed in the coherent dendrite network upon rapid solidification was then performed. This confirms that the as-formed DRF originates from a stress-induced deformation, which also plays an important role in understanding the grain refinement occurring upon rapid solidification of undercooled melts.