Magnetic properties and microstructure evolution of hot-deformed Nd-Fe-B magnets produced by low-pressure spark-plasma sintering

[Display omitted] •Nd-Fe-B hot-deformed magnets were produced by low pressure spark plasma sintering (SPS).•Low pressure SPS gave comparable magnetic properties than the conventional process.•Cone-like shape of the magnet was observed in the initial stages for the first time.•The experiments were perfectly interpreted in the frame of Stoner-Wohlfarth model. We have produced hot-deformed Nd-Fe-B magnets from commercial (MQU-F) Nd-Fe-B ribbons. The spark-plasma-sintering technique was used to deform the samples under low pressures of 40 MPa. The initial stages of the hot-deformation process were investigated in terms of microstructures and magnetic properties. Hot-deformed magnets with different deformation ratios were produced and the dependence of the remanence on the deformation ratio was determined. In the initial stages of the hot-deformation process, a cone-like shape of the magnet was observed for the first time. The experimental data can be qualitatively interpreted by applying the basic Stoner–Wohlfarth model.