Acoustic Emission and Potential Fluctuation During Chloride SCC with Oxide in Its Surface
Acoustic Emission and Potential Fluctuation During Chloride SCC with Oxide in Its Surface
复制标题
表面有氧化物的氯化物SCC过程中的声发射和电位波动
DOI：
10.2472/jsms.55.211
复制
发表时间：
2006
期刊：
影响因子：
--
通讯作者：
M. Takemoto
中科院分区：
文献类型：
--
作者：
A. Yonezu;Yoshiro Taniyama;Hideo Cho;T. Ogawa;M. Takemoto
对敏化304钢板在双向应力状态下的氯化物应力腐蚀开裂（SCC）进行了声发射（AE）和腐蚀电位波动监测。在30mass%MgCl2溶液中（363K），枝状SCC由表面晶粒脱落引发的矩形腐蚀坑产生，并填充氧化铬。声发射和电位的波动同时检测到在腐蚀坑的形成和SCC的扩展。监测两种类型的AE（I型和II型）。具有较高频率成分的I型AE在点蚀生长期间被检测到，并且应该是由于晶间侵蚀引起的表面颗粒脱落而产生的，而具有低频成分的一些II型AE（约12，500计数）在SCC进展时被检测到，并且应该是由氧化物的开裂产生的。虽然在SCC试验过程中检测到的AE不是SCC本身的主要信号，但可以有效地利用次级AE来监测SCC的开始和扩展以及腐蚀电位的波动。
Both the acoustic emission (AE) and corrosion potential fluctuation were monitored for chloride SCC of sensitized Type-304 steel plate under bi-axial stress state. Branched SCCs were produced from rectangular-shaped corrosion pits initiated by falling-off of surface grains and filled with chromium oxide in 30mass% MgCl2 solution (363K). Both the AE and potential fluctuation were simultaneously detected at corrosion pit formation and SCC propagation. Two types of AE (Type-I and Type-II) were monitored. Type-I AEs with higher frequency components were detected during the pit growth and supposed to be produced by falling-off of surface grains due to intergranular attack, while a number of Type-II AEs (about 12,500 counts) with low frequency components were detected at SCC progression and supposed to be produced by cracking of the oxides. Though the AEs detected during SCC test are not the primarily signals from the SCC itself, secondary AE can be usefully utilized to monitor the SCC initiation and propagation as well as the corrosion potential fluctuation.