Reversible Changes of Coercive Force in Sm – Co – Cu – Fe – Zr Alloy for Permanent Magnets Under Cyclic Heat Treatment

Resumo

Causes of reversible changes in the coercivity of alloys for permanent magnets as a result of cyclic heat treatment are analyzed. The magnetic properties and the metallographic and magnetic domain structures of alloy Sm(Co_0.65Fe_0.26Cu_0.07Zr_0.02)₇ are studied as a function of the temperature of interruption of the process cooling. The own results and data of foreign authors are used for developing a scheme of the processes occurring in the alloy in order to explain the mechanism of the “damage – restoration” phenomenon in alloys of the Sm – Co – Cu – Fe – Zr system of type Sm(Co_0.65Fe_0.26Cu_0.07Zr_0.02)₇.