The magnetic characteristics of high-anisotropy Sm(Co1−xCux)5 phases are determined experimentally at 300 K in the range x<0.6. The saturation magnetization Ms decreases and vanishes for SmCo2Cu3. Identical behaviors of Ms and Curie temperature TC versus x are observed in the range x<0.6. For significant Cu substitution rate (x≳0.35), the decrease of the anisotropy field (HA) when x increases is strong. For lower Cu contents, huge values of anisotropy fields make difficult the accurate determination of the substitution effect. The first anisotropy constant K1 is calculated using the available values of HA and Ms. A linear decrease of K1 is observed from SmCo5 to SmCo2Cu3.

Phase relationships in cast Co--Cr surgical implant alloys, heat treated at temperatures from 1180 to 1300 degrees C, are reported. Interdendritic material was identified by selected area diffraction as a quaternary near eutectic mixture between sigma phase, M23C6, M7C3, and fcc Co. Incipient melting and subsequent resolidification of this near-eutectic mixture accounts for observations of behavior at temperatures above 1235 degrees C. At temperatures just below its melting point the interdendritic material initially breaks down to M23C6, which subsequently dissolves in the Co matrix.

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