Theoretical screening of intermetallic ThMn 12 -type phases for new hard-magnetic compounds with low rare earth content

Abstract

We report on theoretical investigations of intermetallic phases derived from the ThMn 12 -type crystal structure. Our computational high-throughput screening (HTS) approach is extended to an estimation of the anisotropy constant K 1, the anisotropy field H a and the energy product (BH) max. The calculation of K 1 is fast since it is based on the crystal field parameters and avoids expensive total-energy calculations with many k-points. Thus the HTS approach allows a very efficient search for hard-magnetic materials for which the magnetization M and the coercive field H c connected to H a represent the key quantities. Besides for NdFe 12 N which has the highest magnetization we report HTS results for several intermetallic phases based on Cerium which are interesting as alternative hard-magnetic phases because Cerium is a less ressource-critical element than Neodymium.