国产不锈钢包壳管与裂变产物的化学相互作用──堆外模拟试验

THE CHEMICAL INTERACTION BETVEEN DOMESTIC STAINLESS STEEL CLADDING AND FISSION PRODUOTSOUT PILE SMULATION TEST

在两种氧势下（分别以Ｃｒ／Ｃｒ２Ｏ３和Ｎｉ／ＮｉＯ模拟），对国内３个单位研制的不锈钢包壳管进行ＦＣＣＩ（燃料包壳化学相互作用）堆外模拟试验。低氧势下，包壳管内壁受裂变产物侵蚀不明显，受侵深度小于包壳管腐蚀设计裕量值。高氧势下，出现了基体腐蚀、晶界侵蚀和剥蚀３种类型兼有的腐蚀形貌，其侵蚀深度超过了腐蚀设计裕量值。化学相互作用深度和晶界渗透深度随氧势增高而加大，晶界渗透深度随着Ｃｓ：Ｔｅ比增大而减小。

Abstract The attack of three kinds of stainless steel clading tubes for FBR by simulation fission pro-ducts Cs,Te,I,Se under different oxygen potential and Te activity is described.The shalfow in-tergranular corrosion or a negligible corrosion of stainless steel tubes was observed under loweroxygen potential(Cr/Cr2O3 buffer)with maximum interaction depth about 28μm or with non-obvious attack under this condition,while the deeper intergranular corrosion and erosive attack ofmatrix were observed under higher oxygen potential(Ni/ NiO buffer)with maximum attackdepth about 100μm. The depth of FCCI and intergranular corrosion increases with the increasingof oxygen potential and decreases with the increasing of Cs:Te ratio from 1.62 to 4.39.