High coercivity, the highest for Cu-free 2:17 Sm-Co ribbons, has been obtained in as-spun (H{sub}c = 21.1 kOe) and short time annealed (H{sub}c = 23.2 kOe) samples of Sm(Co{sub}(bal)Fe{sub}zZr{sub}yBa{sub}x){sub}7.5 alloys, with varying B, Zr, and Fe content (x = 0-0.06, y = 0-0.16, z = 0.08-0.3) and wheel speed. In as-spun samples, the TbCu{sub}7 type structure and in annealed samples the Th{sub}2Zn{sub}17 and CaCu{sub}5 type structures is observed, plus fcc Co as minority phase is observed. Reduced remanence (M{sub}r/M{sub}s) is higher than 0.7. High-temperature magnetic measurements show very good stability above 300 ℃ with coercive field as high as 5.2 kOe at 330 ℃. For annealed Sm(Co{sub}(bal)Fe{sub}0.3Zr{sub}0.02B{sub}0.04){sub}7.5, very good loop squareness and high maximum energy product of 10.7 MGOe have been obtained. Increasing Zr content results in less uniform microstructure of annealed ribbons.
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