鹰潭土壤模拟溶液中SRB+IOB对X100管线钢SCC行为的影响  

Effects of SRB+IOB on Stress Corrosion Cracking of X100 Pipeline Steel in Simulated Solution of Yingtan Soil

作　　者：孙福洋 杨旭 李学顺 SUN Fuyang;YANG Xu;LI Xueshun(Xi’an Special Equipment Inspection Institute,Xi’an 710065,China)

机构地区：[1]西安特种设备检验检测院,陕西西安710065

出　　处：《石油化工腐蚀与防护》2020年第5期1-5,9,共6页Corrosion & Protection In Petrochemical Industry

基　　金：国家市场监督管理总局科技计划项目(2017QK069)。

摘　　要：采用慢应变速率拉伸(SSRT)试验和扫描电镜(SEM)断口分析等手段,研究了鹰潭土壤模拟溶液中SRB+IOB(硫酸盐还原菌+铁氧化菌)对X100管线钢应力腐蚀开裂(SCC)行为的影响。研究结果表明:X100管线钢母材和焊缝试样在无菌和有菌环境下宏观断口均为斜断口,断裂面与拉伸轴方向大致呈45°角,无菌环境下的断口颈缩程度均明显小于有菌环境;在无菌环境下,母材和焊缝断口均为韧性+脆性混合型断口,呈现准解理形貌特征,具有较高的SCC敏感性;在有菌环境下,母材和焊缝断口均为韧性断口,呈现韧窝形貌特征,具有较低的SCC敏感性。同时发现,无菌环境下X100管线钢母材断口侧面的SCC裂纹明显多于有菌环境,也就是说,SRB+IOB的存在抑制了X100管线钢的脆变,使其SCC敏感性降低。Effects of SRB+IOB on stress corrosion cracking of X100 pipeline steel in simulated solution of Yingtan soil were studied by means of SSRT and SEM.In sterile and SRB+IOB simulated solution,it is shown that macro fractures on base material and weld specimens were 45°inclined fracture,necking deformation of fracture in sterile simulated solution was obviously less than that in SRB+IOB simulated solution.In sterile simulated solution,fractures were ductile and brittle,showing quasi-cleavage morphology with high SCC sensitivity;in SRB+IOB simulated solution,fractures were ductile,showing dimple morphology with low SCC sensitivity.It was also found that SCC cracks on fracture side in sterile simulated solution were significantly more than those in SRB+IOB simulated solution,which proved that SRB+IOB inhibited the embrittlement of X100 pipeline steel and reduced its SCC sensitivity.

关 键 词：鹰潭土壤 SRB IOB X100管线钢 SCC SSRT 

分 类 号：TE988.2[石油与天然气工程—石油机械设备]