应用电化学噪声技术(EN)研究了慢应变速率拉伸(SSRT)条件下预制疲劳裂纹的304SS试样在4mol/LNaCl+0.01 mol/LNa2S2O3溶液中的腐蚀行为,EN的时域与频域谱图显示实验后裂纹发生了扩展.扫描Kelvin探针(SKP)分析也证实了裂纹试样经慢拉伸实验后裂纹出现扩展.
This work focuses on the characteristic of electrochemical noise obtaining from 304SS with fatigue pre-cracking 1.002 mm in 4 mol/L NaCl +0.01mol/L Na2S2O3 solutions during SSRT,with time and frequency domain analysis showed the cracking propagated,which was also confirmed by the morphology observations.Moreover,the characteristics of surface morphology image and Volta potential distribution over the surface have been studied before and after the experiments with Kelvin probe.Both the Kelvin and EN can get the same judgment that the cracking propagated after the experiments.
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