(1. 上海大學(xué) 微結(jié)構(gòu)重點(diǎn)實(shí)驗(yàn)室，上海 200444；
2. 上海大學(xué) 材料研究所, 上海 200072)
摘 要: 采用堆外高壓釜腐蝕試驗(yàn)研究添加0.1% Ge和0.5% Ge(質(zhì)量分?jǐn)?shù))對Zr-4合金在360 ℃、0.01 mol/L LiOH水溶液中耐腐蝕性能的影響，用TEM和EDS研究合金的顯微組織和第二相成分。結(jié)果表明：與Zr-4合金相比，添加Ge后合金的耐腐蝕性能顯著提高，但隨著Ge添加量的增加，對耐腐蝕性能的提高作用減弱。當(dāng)Ge含量為0.1%時(shí)，析出密排六方結(jié)構(gòu)的Zr(Fe,Cr)2和Zr(Fe,Cr,Ge)2型第二相；當(dāng)Ge含量達(dá)到0.5%時(shí)，還會析出Zr-Sn-Fe-Cr-Ge和尺寸較大的四方結(jié)構(gòu)Zr3Ge型第二相，添加Ge會使α-Zr基體中固溶的Sn含量降低。固溶在α-Zr中的Ge和尺寸較小的Zr(Fe,Cr)2、Zr(Fe,Cr,Ge)2型第二相可以提高Zr-4+xGe合金的耐腐蝕性能；析出Zr-Sn-Fe-Cr-Ge和尺寸較大的Zr3Ge第二相后會對耐腐蝕性能產(chǎn)生不利的影響。
關(guān)鍵字: Zr-4合金；Ge；耐腐蝕性能；顯微組織
（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
