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用恒电位下的电流-时间记录法研究了Cl-、SO、PO、CrO -离子对非晶态合金亚稳态孔蚀的形核速度、生长速度和再钝化速度的影响.亚稳小孔再钝化过程中电流和时间的关系为:Imax-I=R(t-tmax),其中再钝化速度参数R大致服从对数正态分布.提高Cl-浓度明显加快亚稳态小孔的形核和生长速度,并导致亚稳小孔平均尺寸增大.SO、PO和CrO既能阻碍亚稳小孔形核,也有效降低其生长速度,三种离子抑制亚稳蚀孔形核和生长作用的大小顺序为:CrO>PO>SO.亚稳态小孔的再钝化速度受介质组成变化的影响相对较小.
The effects of Cl-, SO, PO and CrO - ions on the nucleation, growth and reactivation velocities of metastable pitting corrosion of amorphous alloys were investigated by the current-time recording method at a constant potential. The relationship between current and time in the process of metastable pinhole passivation is: Imax-I = R (t-tmax), in which the passivation speed parameter R generally follows the logarithmic normal distribution. Increasing the Cl- concentration significantly accelerates the nucleation and growth rate of metastable pores and leads to an increase in the average size of metastable pores. SO, PO and CrO can not only block the metastable pore nucleation, but also effectively reduce the growth rate. The order of the three kinds of ions inhibiting metastable pore nucleation and growth is CrO> PO> SO. The rate of reactivation of metastable pores is relatively less affected by changes in media composition.