The relationship between the underpotential deposition of zinc and the penetration of hydrogen in armco-iron substrates

Abstract

The underpotential deposition of zinc on ARMCO-iron substrates has been established by cyclic voltammetry. It is shown that the underpotentially deposited zinc submonolayer inhibits the discharge of hydrogen ions onto iron substrates. As a result the penetration of hydrogen into the iron membrane is suppressed, as established by the Devanathan-Stachurski bipolar electrode method. It is shown that the zinc monolayer formed previously by underpotential deposition, reduces by 50–60% the amount of atomic hydrogen included in the membrane during the deposition of zinc at I = 2 A/dm 2. It is stressed that the method is a new approach to the elimination of hydrogen embrittlement during zinc plating of iron articles.