摘要
采用电子背散射衍射(EBSD)、取向成像显微技术(OIM)和X射线残余应力分析技术,通过电化学试验和浸泡腐蚀试验研究了316L不锈钢焊接接头焊缝和母材的特殊晶界分布和表面残余应力分布,以及溶液温度对其耐蚀性的影响。结果表明:316L不锈钢焊接接头焊缝的低重位点阵(CSL)晶界所占的比例比母材的低45%;焊缝和母材的临界点蚀电位分别为0.26 V和0.40 V;在4%FeCl3溶液中,焊缝的腐蚀速率约为母材的2倍,且随着溶液温度的升高,其腐蚀速率逐渐增大;较低比例的低CSL晶界及高的残余拉应力是焊缝优先发生腐蚀的原因。
Using electron backscatter diffraction(EBSD), orientation imaging microscopy(OIM) and X-ray residual stress analysis technique, electrochemical test and immersion corrosion test were used to study the special grain boundary distribution and distribution of weld and base material of 316 L stainless steel welded joint and surface residual stress distribution, and the influence of solution temperature on its corrosion resistance. The results showed that the proportion of low coincidence site lattice(CSL) grain boundaries in the weld of 316 L stainless steel welded joints was 45% lower than that of the base metal. The critical pitting potentials of the weld and base metal were 0.26 V and 0.40 V, respectively. In 4% FeCl3 solution, the corrosion rate of the weld was about twice that of the base metal, and those corrosion rates increased with the increase of solution temperature. Low CSL grain boundary and high residual tensile stress were the reasons for the preferential corrosion of welds.
作者
赵亮
张度宝
涂善东
ZHAO Liang;ZHANG Dubao;TU Shantung(China Nuclear Power Operation Management Co.,Ltd.,Haiyan 314300,China;Life Management Center of Suzhou Thermal Power Research Institute Co.,Ltd.,Suzhou 215004,China;Key Laboratory of Pressure Systems and Saftey Ministry of Education,East China University of Science and Technology,Shanghai 200237,China)
出处
《腐蚀与防护》
CAS
北大核心
2021年第9期49-54,共6页
Corrosion & Protection
关键词
残余应力
电化学试样
浸泡试验
腐蚀速率
residual stress
electrochemical test
immersion test
corrosion rate
