Molybdenum diffusion in thermally treated NANOPERM-type Fe76Mo8Cu1B15 alloy Original Research Article

Mo tracer diffusion in Fe76Mo8Cu1B15 alloy was studied using serial sectioning method in the temperature range 548–648 K. Sputtering by Ar+ ions was applied as a sectioning technique. The measurement was carried out with the ribbon-like samples in as quenched state and in two states after pre-anneal 683 and 743 K/h. Measured concentration profiles consist of two distinct branches suggesting that two diffusion paths are operating. Diffusion coefficients Dv calculated from the near-surface branch were attributed to Mo volume diffusion in amorphous phase, the higher ones, on the other hand are influenced by fast short-circuit diffusion.