CRYSTALLOGRAPHIC ANALYSIS OF ELECTRODEPOSITED ZINC-CRYSTALS ON FE SUBSTRATE

The morphology and the crystallography of eta-zinc crystals electrodep osited on a steel substrate have been examined mainly by scanning elec tron microscopy and X-ray Laue back reflection technique. The morpholo gy of eta-crystals varies with increasing the current density from thi n layered plates to dendrite structures. The layered crystals form dir ectly,on the steel substrate with a specific variant of the Burgers' o rientation relationship described as {110}alpha//(0001)eta and [111]BA Ralpha//[1210]BAR eta. The average size of these layered crystals incr eases with decreasing the angle between the [111]BARalpha//[1210]BAR e ta close-packed direction and the substrate surface. These crystallogr aphic features can be explained in terms of the eta-crystal nucleation at the steps on the substrate surface.