摘要
采用C形环试验研究了在沸腾50％NaOH+0.3％SiO_2溶液中添加Na_2S_2O_3对800合金SCC行为的影响,并结合电化学测量等进行了讨论。Na_2S_2O_3促进800合金在高温碱性溶液中的阳极溶解,使表面钝化膜稳定性下降,这主要归因于对Ni的阳极极化行为的影响;Na_2S_2O_3使800合金的碱性SCC敏感电位范围扩大,开裂速度增加,其中在-40mV(SCE)左右最为敏感。
The effect of additon of Na2S2O3 to boiling solution of 50%NaOH+0.3%SiO2 on SCC of Alloy 800 was investigated using C-ring tests along with anodic polarization measurements for Alloy 800, pure Cr, Ni and Fe. Na2S2O3 was found to stimulate the anodic dissolution and retard the passivation of Alloy 800. This was mainly attributed to the effect of S2O32- on the anodic polarization behavior of Ni. Addition of S2O32- gave rise to acceleration of caustic SCC of Alloy 800, and the maximum cracking rate was observed at ca. -40 mV (SCE).
出处
《中国腐蚀与防护学报》
CAS
CSCD
1998年第1期7-13,共7页
Journal of Chinese Society For Corrosion and Protection
关键词
800合金
C形环试验
硫代硫酸盐
阳极溶解
Alloy 800, Caustic SCC, C-ring test, Thiosulfate, Anodic dissolution
