Sintered Sm/sub 2/(Co, Fe,Cu,Zr)/sub 17/ magnets with light rare earth substitutions

The effects of partial substitution of light rare earths for Sm in (Sm/sub 1-x/R/sub x/)/sub 2/ (Co,Fe,Cu,Zr)/sub 17/ have been investigated where R=Ce, Pr, Nd, Pr/sub 0.5/Nd/sub 0.5/, Ce/sub 0.2/Pr/sub 0.4/Nd/sub 0.4/ and x=0-0.5. Experiments show that both remanence and maximum energy product are improved for x=0.1-0.2, depending upon compositions and heat treatments. For a composition Sm/sub 0.8/R/sub 0.2/(Co/sub 0.633/Fe/sub 0.286/ Cu/sub 0.061/Zr/sub 0.020/)/sub 7.59/ with R=Ce/sub 0.2/Pr/sub 0.4/Nd/sub 0.4/, the authors obtained B/sub r/=11.57 kG, /sub M/H/sub c/=15.5 kOe, /sub B/H/sub c/=10.33 kOe, H/sub k/=10.03 kOe, and (BH)/sub max/=30 MGOe.<
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