Ni铁磁粒子熵和热容量的影响因素分析

Analysis on influence factors of the entropy and the thermal capacity of Ni ferromagnetic particle

应用统计物理和固体理论,推导了外磁场中镍铁磁粒子的熵、热容量等热力学函数,并利用Mathematica软件进行了数值计算.结果表明:镍铁磁粒子的磁矩与外磁场相互作用引起的熵随温度升高而减小,随外磁场增大而增大;其热容量随温度的升高而增大,随外磁场强度的增大而减小;晶格振动和表面自由能引起的熵和热容量均随温度的升高而增大;温度较低时变化趋势更为显著.

With the theory of statistical physics and solid physics, the thermodynamic functions, the entropy and the thermal capacity of Ni ferromagnetic particle in external magnetic field have been figured out, and the numerical simulation have been analyzed by Mathematica software. The results show that： the entropy of Ni ferromagnetic particle caused by the interaction of magnetic moments and external magnetic field will decrease with the increase of the temperature and will augment with the increase of the external magnetic field, the thermal capacity will increase with the augment of the temperature and will decrease with the increase of the external magnetic field intensity, the entropy and the thermal capacity of caused by both the crystal lattice vibration and the surface free energy will increase with the increase of the temperature, the change trend becomes more remarkable when the low temperature.