NdFeB magnets present high magnetocrystalline anisotropy that leads to outstanding magnetic properties. This anisotropy is also present during the sintering and plays a role into the mechanisms driving the densification. Sintering was studied along and perpendicular to the easy magnetization axis for an optimized thermal cycle leading to high magnetic properties and full densification. The parallel strain rate is significantly lower than the perpendicular strain rate, especially at low temperature . The sintering kinetics at high temperature would be mainly controlled by solid state diffusion with a high apparent activation energy (450-474kJ/mol).