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用 AES 原位加热的方法研究了 Ni_(84)P_(16)非晶合金中磷原子的表面偏析现象。在实验温度范围内,磷向自由表面的偏析是由体扩散控制的,表面浓度 C_S 随退火时间 t 的变化符合 Hoffmann—Erlewein关系(H—E关系)。在250—350℃温区内,磷原子单独向表面偏析,扩散系数 D 位于1.1×10~(-24)—9.0×10~(-22)m~2s~(-1)之间,D 与 T 符合 Arrhenius 关系,其中指数前因子 D_0=2.81×10~(-6)m~2s~_(-1),扩散激活能E_0=1.70eV。在380℃退火时,晶化产生的晶界加速 P 偏析,同时促进 Ni 向自由表面扩散。
The surface segregation of phosphorus atoms in Ni_ (84) P_ (16) amorphous alloys was investigated by AES in situ heating. The segregation of phosphorus to the free surface is controlled by bulk diffusion within the experimental temperature range. The change of surface concentration C_S with annealing time t conforms to the Hoffmann-Erlewein relationship (H-E relationship). In the temperature range of 250-350 ℃, the phosphorus atom segregates to the surface alone, and the diffusion coefficient D lies between 1.1 × 10 ~ (-24) -9.0 × 10 ~ (-22) m ~ 2s ~ (-1) T is consistent with the Arrhenius relationship, in which the exponential factor D_0 = 2.81 × 10 -6 m -2 s -1, and the diffusion activation energy E_0 = 1.70 eV. When annealed at 380 ° C, the grain boundaries produced by crystallization accelerated P segregation and promoted the diffusion of Ni to the free surface.