1992 Volume 43 Issue 12 Pages 1146-1150
A study has been made of the electrochemical properties and of the microscopic characteristics such as surface composition and structure for oxygen-implanted iron surface layers. Oxygen implantation into pure iron was performed at fluences ranging from 1.4×10-2 to 2.2×10-1C·cm-2 and an accelelation voltage of 80kV, using non-massseparated ions. Electrochemical reaction was measured by multi-sweep cyclic voltammetry in an acetate buffer solution of pH=5.0. AES, RBS, XPS and XRD were used to analyze the depth dependence of atomic fractions and chemical bonding states, and the crystal structure of implanted layers. The atomic fraction of oxygen saturated at approximately 60% to form a trapezoidal distribution at high doses, and oxygen atoms combined with iron to form crystalline oxides. The peak anodic dissolution current density for iron subjected to high-dose oxygen implantation was approximately 1/20 that for pure iron, owing to the formation of surface layers with a trapezoidal oxygen distribution consisting of iron oxides.
