闭塞区中Ni^(2+)对核级304不锈钢高温水氧化行为的影响  

EFFECT OF Ni^(2+) IN OCCLUDED VOLUME ON THE OXIDATION BEHAVIOR OF 304 STAINLESS STEEL IN HIGH TEMPERATURE WATER

作　　者：匡文军[1,2] 吴欣强[1,2] 韩恩厚[1,2] 

机构地区：[1]中国科学院金属研究所金属腐蚀与防护国家重点实验室,沈阳110016 [2]中国科学院金属研究所辽宁省核电材料安全与评价技术重点实验室,沈阳110016

出　　处：《金属学报》2011年第7期927-931,共5页Acta Metallurgica Sinica

基　　金：国家自然科学基金项日50971113;国家重点基础研究发展计划项目2011CB610506;国家科技重大专项课题2011ZX06004010资助~~

摘　　要：核电站服役的高温高压水回路中闭塞区的流动不充分,可能产生异常水化学条件而导致材料服役性能弱化.本文利用国产核级304不锈钢制备了一种简单的模拟闭塞区样品,放入含有Ni^(2+)的高温含氧水中浸泡并对生成的氧化膜进行表征.结果表明:闭塞区从外到内氧化膜外层中的尖晶石结构相的比例逐渐减小,而赤铁矿结构相的比例逐渐增大,模表层的Ni含量逐渐降低.分析表明,Ni^(2+)浓度会显著影响核级不锈钢的氧化行为,闭塞结构会在一定程度上阻碍本体溶液中的Ni^(2+)向闭塞区内扩散,使Ni^(2+)沿闭塞区深度方向形成浓度梯度.导致氧化膜的生长特征沿梯度方向发生明显变化.In the occluded volume of high temperature pressurized water loop in nuclear power plants, poor-controlled water chemistry due to sluggish flowage could induce accelerated degradation of structural materials. In this paper, an occluded volume shaped nuclear-grade 304 stainless steel sample was immersed in oxygenated high temperature water containing a certain concentration of Ni2＋. It was found that from the outer to the inner side of the sample, the proportion of spinel in the oxide film decreased while that of hematite increased and Ni content in the outer oxide film decreased. It was thought that the concentration of Ni2＋ could influence the oxidation behavior of material significantly. The occluded volume could impede the inward diffusion of Ni2＋, causing a concentration gradient of Ni2＋ along depth of the volume and gradual change of oxide film characteristic.

关 键 词：核级不锈钢 高温高压水 闭塞区 NI2+ 氧化膜 

分 类 号：TG172.82[金属学及工艺—金属表面处理]