Enhanced microwave absorption performance of Sm2Fe14B microflakes with adjustable bianisotropy

Introducing adjustable bianisotropy in traditional soft magnetic materials is promising for achieving high-frequency ferromagnetic resonances and microwave absorption performance. Here, the low-cost and large-scale Sm₂Fe₁₄B microflakes with adjustable bianisotropy were obtained by solid-phase sintering method with hot-pressing technology. The performance of Lorentz transmission electron microscopy and the theoretical simulations clarify that the bianisotropy is composed of shape anisotropy and magnetocrystalline anisotropy, which can be manipulated by isothermal quenching temperatures and different pressure conditions. The high-frequency electromagnetic behavior has been effectively adjusted. The real part of the complex permeability can reach 1.45 at 11.5 GHz, and the minimum reflection loss is $-$63.0 dB at 1.64 mm with a centered effective absorption bandwith of 3.23 GHz at 1.13 mm. This study offers insight into the preparation of high-frequency magnetic loss materials by inducing adjustable bianisotropy in traditional soft magnetic materials and facilitates the application of traditional low-cost soft magnetic materials in microwave absorption applications.