The reversal of magnetisation has been studied in a three-dimensional Ising ferromagnet by Monte Carlo simulation with Metropolis single spin flip algorithm using random updating scheme. The outer layers are considered as surface. The surface interacts with core with a relative ferromagnetic interaction strength. Depending on the relative interaction strength, the time of reversal of the surface was found to be different from that of the bulk. For weaker relative strength, surface reversal was found to be faster than that of bulk and vice versa for stronger relative interaction strength. A critical value (\(R_c\)) of relative interaction strength provides same time of reversal of surface and bulk. This critical relative interaction strength was found to be a function of the temperature (T) and applied magnetic field (h). The scaling relation \(R_c \sim h^{-\beta }f(Th^{\alpha })\), where \(\alpha =0.23\pm 0.01\) and \(\beta = -0.06\pm 0.01\), has been proposed, numerically by the method of data collapse. The metastable volume fractions, for both surface and bulk, were found to follow the Avrami’s law. The critical relative interaction strength (\(R_c\)) has been observed to decrease in an exponential (\(e^{bL^{-1.5}})\) fashion with the system size (L).

通过使用随机更新方案的 Metropolis 单自旋翻转算法，通过蒙特卡罗模拟在三维 Ising 铁磁体中研究了磁化的反转。外层被视为表面。表面以相对铁磁相互作用强度与磁芯相互作用。根据相对相互作用强度，发现表面反转的时间与本体的反转时间不同。对于较弱的相对强度，发现表面反转比块体的反转要快，反之亦然对于较强的相对相互作用强度。相对相互作用强度的临界值 ( \(R_c\) ) 提供相同的表面和体积反转时间。发现该临界相对相互作用强度是温度的函数（T) 和外加磁场 ( h )。缩放关系\(R_c \sim h^{-\beta }f(Th^{\alpha })\)，其中\(\alpha =0.23\pm 0.01\)和\(\beta = -0.06\pm 0.01 \)，已经提出，通过数据折叠的方法进行数值计算。发现表面和体积的亚稳态体积分数遵循 Avrami 定律。已经观察到临界相对相互作用强度（\(R_c\)）随着系统大小（L）以指数（\(e^{bL^{-1.5}})\）方式降低。