Abstract: The measurement and a self-made instrument of the saturation magnetostriction of amorphous ribbon by the small angle magnetization rotation （SAMR） method are investigated. Dependence of the voltage of the second harmonic wave on alternating current and applied frequency is measured. Under the optimal measurement condition, the saturated saturation magnetostriction coefficient （As） of FeFe65～70Co15～20Si1～3B12～15, amorphous ribbon is measured and the λa of 1.74×10^-5 is obtained.

Key words: amorphous ribbon, SAMR, saturation magnetostriction coefficient