杂质元素(C,Si)对Zr-4合金板材微观结构及耐腐蚀性能的影响  

Effect of Impurity Elements(C, Si) on Microstructure and Corrosion Resistance of Zircaloy-4 Sheet

作　　者：储林华 袁改焕[1] 姚美意[2] 高博[1] 徐诗彤 周邦新[2] Chu Linhua;Yuan Gaihuan;Yao Meiyi;Gao Bo;Xu Shitong;Zhou Bangxin(State Nuclear Bao Ti Zirconium Industry Company,National R&D Center of Nuclear Grade Zirconium Material,Shaanxi Key Laboratory of Nuclear Grade Zirconium Material,Baoji 721013,China;Shanghai University,Shanghai 200072,China)

机构地区：[1]国核宝钛锆业股份公司,国家能源核级锆材研发中心,陕西省核级锆材重点实验室,陕西宝鸡721013 [2]上海大学,上海200072

出　　处：《稀有金属材料与工程》2020年第10期3338-3346,共9页Rare Metal Materials and Engineering

摘　　要：在ASTM标准范围内,利用板材试样研究了杂质元素对Zr-4合金微观结构和耐腐蚀性能的影响。结果表明,降低C含量、提高Si含量,有利于改善Zr-4合金在400℃蒸汽下的耐均匀腐蚀性能。微观分析显示,元素C易于以Zr-C形式在基体相表面富集,其主要通过左右第二相粒子的析出进而影响耐腐蚀性能。C含量越低,淬火过程中坯料越倾向于形成平行板条(PP)结构;C含量越高,越易于形成网篮(BW)结构;而第二相粒子更易于沿平行板条结构的边界析出。当淬火温度低于1200℃时,Si含量对于是否形成平行板条结构没有明显影响。同时,三维原子探针(3DAP)分析显示,Si倾向于以SiO2形式在第二相粒子周围偏聚,推迟或延缓了第二相粒子的氧化过程,进而提升了Zr-4合金的耐腐蚀性能。In the range of ASTM,the effect of impurity elements on microstructure and corrosion resistance of Zr-4 alloy was studied by using sheet samples.The results show that reducing carbon content and increasing silicon content are beneficial to improve uniform corrosion resistance of Zr-4 alloy at 400℃steam.Microscopic analysis shows that carbon is easily enriched in the form of Zr-C on the matrix phase,and it mainly affects the corrosion resistance by influencing the precipitation of second phase particles.The lower its content is,the easier it is to form the parallel plate(PP)structure during quenching,and the higher its content is,the more likely it is to form basket weave(BW)structure,while the second phase particles are easier to precipitate along the grain boundary of PP structure.When quenching temperature is lower than 1200℃,silicon content has no obvious effect on the formation of PP structure.Meanwhile,three-dimensional atom probe(3 DAP)analysis shows that silicon tends to agglomerate in the form of SiO2 around the second phase particles,and delays or weakens the oxidation of second phase particles,thus improving the corrosion resistance of Zr-4 alloy.

关 键 词：锆合金 杂质 微观组织 均匀腐蚀 β相固溶处理 第二相粒子 偏聚 

分 类 号：TG146.414[一般工业技术—材料科学与工程]