Strain-induced coercivity enhancement in Mn51Al46C3 flakes prepared by surfactant-assisted ball milling

• We report the preparation of Mn51Al46C3 flakes employing different processing routes.
• A correlation between the coercivity and internal strain has been established.
• The variation in the lattice parameters is attributed to the internal strain.
• The defects and the strained areas act as the source of domain wall pinning.

A correlation between the coercivity and internal strain has been established for as-milled τ-phase Mn51Al46C3 flakes prepared by surfactant-assisted ball milling (SABM). The variation in the lattice parameters is attributed to the internal strain induced by the continuous high speed collision from the balls during the SABM process. A high coercivity up to 266.2 kA/m was accompanied by a relatively large residual strain, due to the domain wall pinning effect of the defects and the associated strained areas. The effect of strain on the coercivity of MnAl flakes provides a good approach for achieving highly tunable coercivity for the magnetic materials.