非晶态Fe13Ni67.2P4.5B15.3合金的临界现象

本文报道非晶态Fe₁₃Ni_67.2P_4.5B_15.3合金的磁化强度与温度和磁场关系的测量结果。在居里温度附近样品的磁特性符合二级相变规律,得到临界指数β=0.39±0.02,γ=1.56±0.06,δ=5.20±0.1,样品的居里温度T_c=(180.4±0.2)K。在实验误差范围内,临界指数β,γ,δ满足γ=β(δ-1)关系,在168—192K温度范围,实验数据满足二级相变的磁状态方程。当T>270K时,样品顺磁磁化率服从居里-外斯定律,由居里-外斯常数c计算出有效顺磁磁矩P_eff=3.19 μ_B。 关键词：

CRITICAL PHENOMENA OF AMORPHOUS Fe13Ni67.2P4.5B15.3 ALLOYS

Results of the magnetization measurements performed on the amorphous Fe₁₃Ni_67.2P_4.5B_15.3 alloy in the temperature range 1.5 to 300 K in fields up to 40 kOe are reported. The behaviour near the Curie temperature is found to obey second-order phase transition laws with critical indices: β=0.39±0.02;γ=1.56±0.06; δ=5.20±0.1, and the ferromagnetic Curie temperature T_c = (180.4 ± 0.2)K. Within experimental error the critical indices satisfy the scaling law relationship γ=β(δ-l). The data satisfy the magnetic equation of state characteristic of a second-order phase transition in the temperature range 168 to 192 K. Above 270 K, the paramagnetic susceptibility obeys the Curie-Weiss law. From the Curie constant c, we obtain the effective magnetic moment p_eff=3.19 μ_B.