Ribbons of Super Sendust ($Al_{7.5}Si_{10.8}Ni_{3.0}$ bal. Fe in at.%) and $Al_{7.5}Si_{10.8}Ni_{3.0+x}Cr_x$ bal.Fe from x=0 to 6 were made by the melt spinning rapid solidification method. The dimension of ribbons was 25 to 50 micron thick and was 0.7-1.5 mm wide. Ni content was increased with Cr addition so that the average valence electrons remained constant in the alloys.
The magnetic properties of as-rapidly solidified Super Sendust ribbon were $B_3=8900$ Gauss, $\mu_m$ = 5700, Hc = 0.7 Oe. However, further addition of Ni and Cr deteriorated the magnetic properties of ribbons. After magnetic annealing the magnetic properties of ribbons slightly improved : $B_3$ = 10800 Gauss, $\mu_m$ = 14000, Hc = 0.35 Oe. The combined effect of Ni and Cr addition and magnetic annealing was not so good. Electrical resistivity of as-solidified Super Sendust ribbon was 108 micro-ohm-cm and after annealing at 1200℃ for 3 hours it became 104 micro-ohm-cm. The addition of Ni and Cr increased the resistivity of as-rapidly solidified ribbon to 143 micron-ohm-cm, but Cr addition of more than 4 at.% decreased the resistivity after annealing at 1200℃ for 3 hours.
