It was found that sintered alloys having a composition of approximatelyz=8 in Sm(Co0.85Fe0.05Cu0.10)zexhibit a high coercive force on the order of 10 kOe, for 5–10‐&mgr;m average grain size. Magnetization and demagnetization curves showed that the coercive force is controlled by a nucleation process. Attempts were made to achieve a high density without serious grain growth by means of high‐pressure isostatic compaction and hot pressing, resulting in 96% of the density and 7‐&mgr;m average grain size. With this approach,Br=10.3kG,IHc=10.2 kOe, and a maximum energy product of 22.0 MG Oe were achieved.