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Movement of multiple markers (M-Ms) embedded in the Cu end member of a Cu/Zn multiple phases diffusion couple (M-couple) has been experimentally investigated at 623 K and the alignment of the M-Ms after diffusion anneal was reproduced by the numerical analysis that the authors have previously reported. Two intermediate phases, c and e, were found in the Cu/Zn M-couple. The M-Ms bent toward Zn side at Cu/c phase interface and show almost a linear line in the c phase. They again bent at c/e interface toward Zn side. The Kirkendall marker position, X k , locates in the e phase layer. From this result, ratio, R = D Zn /D Cu , of the intrinsic diffusion coefficients with respect to the mole fixed frame of reference was determined to be about 46 at X k . On the assumption of a constant value of R = 46 in the e phase and appropriate constant values of R = 10-1000 in the c phase, alignments of M-Ms after diffusion anneal were numerically reproduced. By fitting the alignment of M-Ms obtained numerically on the experimental result, the value R in c phase is estimated to be very large value of 500.

By using the melt spinning techniques, the Fe 63 Co 32 Gd 5 alloy ribbons with 15−50 m in thickness and 3−7 mm in width were prepared at the wheel speeds of 15, 20, 25 and 35 m/s. The rapid solidification microstructures were characterized by three layers, the middle layer of which reaches 80% thickness and forms the column grain of (Fe,Co) solid with Gd solution. Grain refinement takes place with the increase of the wheel speed. And after 0.5 h heat treatment at 823 K, the ribbon thickness becomes larger and the middle layer of column grain is very orderly perpendicular to the ribbon plane. The coercivity of quenched and annealed Fe 63 Co 32 Gd 5 ribbons both have the inflection point at the wheel speed of 20 m/s, and the tendency is declining. The heat treatment processing makes the coercivity become lower by improving the order of (Fe,Co) 17 Gd 2 compound. The saturation magnetization of quenched ribbons increases with the enhancement of wheel speed, whereas that of annealed ones decreases firstly and then increases. The minimum coercivity is 5.30×10 3 A/m and the maximum saturation magnetization is 163.62 A·m 2 /kg, which is obtained in the conditions of the wheel speed of 35 m/s and 0.5 h heat treatment at the temperature of 823 K.