| Abstract
| - Two types of additives in hot-dip galvanizing, effective additives Ni, V, and Ti usedindustrially to reduce the coating thickness of zinc−iron, and noneffective additives Mg,Sn, and Ag showing quite different behavior from the former, were studied with densityfunctional theory calculations by using cluster models. The optimized geometric configurations, total energy, electronic density of states, and electronic charge distributions for theadditive−zinc associates were obtained. Results indicated (1) the effective additives havemuch stronger bonding energy with zinc than the noneffective additives, (2) the electroniccharges significantly shift from the zinc atoms to the Ni, V, or Ti atoms, while only a littleshift to the Mg, Ag, or Sn atoms occurs, and (3) the Fermi energy level and the band gap ofzinc clusters obviously change, owing to adding Ni, V, or Ti, but these effects do not occurfor the second type of additives. On the basis of the calculated results, the underlyingmechanism of additive effect on the formation of Fe−Zn intermetallics (and/or coatingthickness) was proposed.
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