Pii: S1359-6454(99)00157-3
نویسنده
چکیده
ÐBoth experimental and simulation results have indicated the deviation from Arrhenius law of the diusion coecient of hydrogen in metallic glasses. This deviation was traditionally explained by the existence of various kinds of jumps or in terms of continuous distributions of activation energies due to dierent kinds of disorder. A new model is suggested, which relates this deviation to the temperature dependence of the short-range order (SRO). The suggested model is applied to simulate the diusion behavior of hydrogen in dilute amorphous Fe±H, Fe±Si±H and Fe±B±H alloys. The eect of the alloying elements on the activation energy of hydrogen diusion in amorphous iron is discussed in terms of their electronic structure and mean volume. # 1999 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved.
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