Magnetic hardening of Zr2Co11:(Ti, Si) nanomaterials

• Ti addition has a positive effect on energy product through refinement of structure.
• Ti occupies Zr site.
• However, Si enters Co site.
• It is expected that the combinatorial addition of Ti and Si will further improve magnetic properties.

The role of Ti and Si additions in the magnetic hardening of rapidly-quenched Zr2Co11-based nanomaterials has been investigated. Nanocrystalline Zr17−xTixCo83 and Zr18Co82−ySiy are mainly composed of rhombohedral Zr2Co11 and a small amount of orthorhombic Zr2Co11, hcp Co and cubic Zr6Co23. Ti addition decreases the mean grain size of the magnetic phases, and thus increases coercivity and energy product from 1.6 kOe and 1.9 MGOe for x = 0 to 2.6 kOe and 3.9 MGOe for x = 2, respectively. Si addition enhances the anisotropy field of the hard phase which increases the coercivity but slightly decreases the magnetization. This work shows that Ti has a positive effect on energy product through refinement of structure.