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The effects of Fe content as well as the dc or ac stress current annealing conditions (current density, annealing time, and tensile stress) on the magnetoelastic behavior of amorphous Co72.5-xFexSi12.5B15 (x=0, 3, 4.35, 5, and 7. at.%) glass-covered wires have been investigated. The saturation magnetostriction at zero applied stress λs (0) in the as-cast state of the samples is about -2.8×10-6; -0.6×10-6; -0.11×10-6; 0.36×10-6, and 0.9×10-6 for x=0, 3, 4.35, 5, and 7 at.% Fe, respectively. For nearly zero magnetostrictive amorphous Co68.15Fe4.35Si12.5B15 glass-covered wire, after stress current annealing λs (0) changes from small negative to small positive values. The positive λs (0) values are obtained after about 3-8 min annealing time for current densities higher than 130×106 A/m2. The ac stress current annealing leads to an increase with maximum 60% of the maximum saturation magnetostriction value λs (0)max (depending on the frequency value) in comparison with dc annealing for the same current density, treatment time, and tensile stress. For alloys with x=0, 3, 5, and 7 at.% Fe, after dc or ac stress current annealing with (60-180)×106 A/m2, under 300-800 MPa, a modification up to 10% in λs (0) values was observed (the absolute value for negative magnetostrictive samples decreases while for positive magnetostrictive samples increases).