Revelation of the high hardness and spin glass behavior in the novel magnetic material CrFeB

Abstract

Ternary transition metal borides (TTMBs) will break materials application limitation in harsh service environments, owing to their structure versatility and high component tunable ability. Herein, we reported a solid solution boride CrFeB synthesized by high pressure and high temperature method. CrFeB yields an asymptotic hardness of 14.2 GPa and thermal stability temperature is up to 1250 K. DC magnetic susceptibility measurements revealed that there is a separation between zero-field cooled and field cooled curve at around 5 K, which indicated the spin glass behavior for CrFeB. Temperature dependence AC susceptibility analysis gives further evidence that the freezing temperature increases with frequency following Vogel-Fulcher law. On the basis of XPS results and first-principle calculations, we speculate that the complex magnetic behaviors may derive from the short-range magnetic exchange of same occupation sites two metal atoms. Cr and Fe atoms tend to have opposite magnetic moments in these short-range exchange behaviors. The intrinsic magnetic disorder and short-range frustration lead to spin random freezing of CrFeB at low temperatures, which conforms to typical spin glass characteristics. These results will contribute to understanding the complex magnetism behavior of CrFeB and provides a new idea to design multifunctional TTMBs.