(1. 上海大学 微结构重点实验室，上海 200444；
2. 上海大学 材料研究所, 上海 200072)
摘 要: 采用堆外高压釜腐蚀试验研究添加0.1% Ge和0.5% Ge(质量分数)对Zr-4合金在360 ℃、0.01 mol/L LiOH水溶液中耐腐蚀性能的影响，用TEM和EDS研究合金的显微组织和第二相成分。结果表明：与Zr-4合金相比，添加Ge后合金的耐腐蚀性能显著提高，但随着Ge添加量的增加，对耐腐蚀性能的提高作用减弱。当Ge含量为0.1%时，析出密排六方结构的Zr(Fe,Cr)2和Zr(Fe,Cr,Ge)2型第二相；当Ge含量达到0.5%时，还会析出Zr-Sn-Fe-Cr-Ge和尺寸较大的四方结构Zr3Ge型第二相，添加Ge会使α-Zr基体中固溶的Sn含量降低。固溶在α-Zr中的Ge和尺寸较小的Zr(Fe,Cr)2、Zr(Fe,Cr,Ge)2型第二相可以提高Zr-4+xGe合金的耐腐蚀性能；析出Zr-Sn-Fe-Cr-Ge和尺寸较大的Zr3Ge第二相后会对耐腐蚀性能产生不利的影响。
关键字: Zr-4合金；Ge；耐腐蚀性能；显微组织
（1. Laboratory for Microstructures, Shanghai University, Shanghai 200444, China;
2. Institute of Materials, Shanghai University, Shanghai 200072, China）
Abstract:In order to investigate the effect of Ge addition on the corrosion resistance of zircaloy-4 (Zr-4) alloy, the corrosion performance of Zr-4+xGe (x= 0.1%, 0.5%, mass fraction) was studied in lithiated solution with 0.01 mol/L LiOH at 360 ℃ by out reactor autoclave testing. The microstructures of the alloys and the compositions of the second phase particles (SPPs) were investigated by TEM and EDS. The results show that compared with Zr-4 alloy, the corrosion resistances of Zr-4+xGe alloys containing 0.1% and 0.5% Ge are markedly improved, while the corrosion resistances decrease slightly with the increase of Ge addition. The addition of Ge decreases the solid solution content of Sn in the α-Zr matrix. When the Ge content is 0.1%, the second phase particles precipitate as Zr(Fe,Cr)2 and Zr(Fe,Cr,Ge)2 in Zr-4+xGe alloy. When the Ge content reaches 0.5%, a part of Ge precipitates as Zr-Sn-Fe-Cr-Ge or Zr3Ge SPPs. The solid solution of Ge in the α-Zr matrix and small SPPs of Zr(Fe,Cr)2 and Zr(Fe,Cr,Ge)2 are beneficial to the corrosion resistance of Zr-4+xGe alloy, while the corrosion resistance decreases due to the precipitation of Zr-Sn-Fe-Cr-Ge and SPPs of Zr3Ge with large size.
Key words: Zr-4 alloy; Ge; corrosion performance; microstructure
