Effects of cell morphology and macrosegregation of directionally solidified Zn-rich Zn-Cu alloys on the resulting microhardness

► Monophasic and hipoperitectic Zn-rich Zn-Cu alloys are directionally solidified. ► The correlation microstructure/transient solidification parameters are fundamental. ► Experimental growth laws relating cellular spacing to the cooling rate are proposed. ► Hall-Petch type equations are proposed relating hardness to the cell spacing.