Hf对ODS-FeCrAl合金微观组织及性能的影响  

Effect of Hf on Microstructure and Property of ODS-FeCrAl Alloy

作　　者：吴飒建 李静[1] 刘实[1] WU Sajian;LI Jing;LIU Shi(Key Laboratory of Nuclear Materials and Safety Assessment,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China;School of Materials Science and Engineering,University of Science and Technology of China,Shenyang 110016,China)

机构地区：[1]中国科学院金属研究所核用材料与安全评价重点实验室,辽宁沈阳110016 [2]中国科学技术大学材料科学与工程学院,辽宁沈阳110016

出　　处：《原子能科学技术》2020年第4期648-656,共9页Atomic Energy Science and Technology

基　　金：沈阳科技局资助项目(Y17-0-022)。

摘　　要：为研究少量添加的Hf对ODS-FeCrAl合金微观组织及性能的影响,通过机械合金化和后续的热等静压工艺研制两种14Cr-ODS-FeCrAl合金,对其进行微观结构、力学性能、1200℃空气抗氧化性能和1200℃水蒸气抗腐蚀性能测试。TEM结果表明,两种合金中YAlO3氧化物析出相细小弥散,而Hf的添加促进合金基体中生成颗粒尺寸更加细小的Y2Hf2O7纳米氧化物。由于纳米氧化物Orowan的强化机制,两种合金均具有优异的室温与高温力学性能。XRD和SEM结果表明,两种合金经过1200℃空气氧化与1200℃水蒸气腐蚀后,表面均形成均匀致密的α-Al2O3膜,对合金起保护作用。Hf添加有利于合金在1200℃水蒸气腐蚀条件下形成更加均匀的α-Al2O3膜,抑制Al3+的向外扩散,避免合金内部晶界处形成空穴。In order to study the effect of a small amount of Hf on the microstructure and property of ODS-FeCrAl alloy,two kinds of 14 Cr-ODS-FeCrAl alloys were prepared by mechanical alloying and subsequent hot isostatic pressing.The microstructure,mechanical property,air oxidation resistance at 1200℃and steam corrosion resistance at 1200℃were tested.TEM results show that the oxide precipitate phases of YAlO3 oxide in the two kinds of alloys are fine and dispersed,while the addition of Hf promotes the formation of Y2Hf2O7 nano-oxide with finer particle size in the alloy matrix.Due to the Orowan strengthening mechanism,the two kinds of alloys have excellent mechanical property at room temperature and high temperature.The results of XRD and SEM show that the surface of the two kinds of alloys form uniform and denseα-Al2O3 film after air oxidation at 1200℃and steam corrosion at 1200℃,which protects the alloy.The addition of Hf is beneficial to form more uniformα-Al2O3 films under the condition of 1200℃steam corrosion,to inhibit the outward diffusion of Al3+,and to avoid the formation of cavities at the internal grain boundary of the alloy.

关 键 词：ODS合金 显微组织 氧化物析出相 力学性能 高温空气氧化 高温水蒸气腐蚀 

分 类 号：TG142.13[一般工业技术—材料科学与工程]