Micromagnetic simulation of the pinning and depinning process in permanent magnets

We have studied the pinning of magnetic domain walls on a simplified model of the cell structure of Sm(Co,Fe,Cu,Zr)/sub z/ precipitation hardened magnets. The pinning field strongly depends on the thickness of the intercellular phase if it is smaller than the domain wall width. Its maximum value has been verified with a one-dimensional analytical model. The cell structure plays an important role in the depinning process and it has been found that the pinning field depends linearly on the relative thickness of the intercellular phase. This behavior is universal for attractive and repulsive pinning.