Hot deformed anisotropic nanocrystalline NdFeB based magnets prepared from spark plasma sintered melt spun powders

•Microstructure evolution and its influence on the magnetic properties were investigated.•The increase of stray field and weakening of domain-wall pinning effects were the main reasons of the decrease of the coercivity with increasing the compression ratio.•The influences of non-uniform plastic deformation on the microstructure and magnetic properties were investigated.•Magnetic properties and temperature coefficient of coercivity are indeed very promising without heavy rare earth elements.