The behavior of yttrium implants in H13 steel under high temperature oxidation

The penetration depth of yttrium ions extracted at 30 kV from a metal vapor vacuum arc (MEVVA) source reaches approximately 50 nm in H13 steel. For a pre-set dose of 3×1017 cm−2, the retained dose decreases (1.04×1017–6.2×1016 cm−2) with increasing beam flux (25–76 μA cm−2). During high temperature (600–800°C) oxidation, yttrium implants have no change in quantity, but migrate inwards and redistribute themselves. As the dose is increased (up to 1×1018 cm−2) in-going yttrium is redistributed almost uniformly within the oxidation scale; when the beam flux is increased the peak of yttrium profile shifts to a much deeper position (245 nm for 76 μA cm−2). Yttrium redistribution is not sensitive to oxidation time. A tentative explanation is presented.