Temperature-dependent magnetization of nanocrystalline Ni has been simulated with the stochastic Landau–Lifshitz–Gilbert theory.

First order and second order surface anisotropy energy due to the grain boundaries has been included in the model.

First-order grain boundary anisotropy constant dominates at low temperatures and it decreases with increasing temperature.

Second-order grain boundary anisotropy constant is negligibly small at low temperatures and it increases with increasing temperature.