15Ni-15Cr ODS钢的微观结构与力学性能  

Microstructure and mechanical properties of 15Ni-15Cr oxide dispersion strengthened austenitic steel

作　　者：赵瑞林 贾皓东 曹书光 佟振峰 周张健[1] ZHAO Rui-lin;JIA Hao-dong;CAO Shu-guang;TONG Zhen-feng;ZHOU Zhang-jian(School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China;School of Nuclear Science and Engineering,North China Electric Power University,Beijing 102206,China)

机构地区：[1]北京科技大学材料科学与工程学院,北京100083 [2]华北电力大学核科学与工程学院,北京102206

出　　处：《工程科学学报》2023年第1期107-116,共10页Chinese Journal of Engineering

基　　金：国家自然科学基金资助项目(U1967212)。

摘　　要：氧化物弥散强化(Oxide dispersion strengthened,ODS)钢因其良好的高温力学性能和抗辐照性能被认为是钠冷快堆包壳材料的重要候选材料.本文通过机械合金化以及热等静压和锻造工艺制备了15Ni‒15Cr ODS奥氏体钢,并且采用相同工艺制备了不加氧化物的15Ni‒15Cr奥氏体钢作为参比材料.利用透射电镜对样品的微观结构进行分析,发现15Ni‒15Cr和15Ni‒15Cr ODS奥氏体钢晶粒尺寸分别为0.75和0.5μm.15Ni‒15Cr ODS奥氏体钢中分布的氧化物弥散粒子主要为δ-Y_(4)Zr_(3)O_(12)以及少量的Al_(2)O_(3).15Ni‒15Cr ODS奥氏体钢中氧化物弥散粒子的平均粒径为12.8 nm、数密度5.5×10^(22)m^(−3)、粒子间距26 nm.相比于15Ni‒15Cr奥氏体钢,15Ni‒15Cr ODS奥氏体钢具有更高的强度,但是高温塑性有所降低.15Ni‒15Cr ODS奥氏体钢的室温断裂机制为韧性断裂,高温断裂机制为韧–脆混合断裂.The development of advanced cladding material with improved service performance is a key issue in engineering applications of sodium-cooled fast reactors.At present,the cladding materials of sodium-cooled fast reactors are mainly AISI type 316 or 15-15Ti austenitic stainless steel obtained by the traditional smelting method.However,the high-temperature mechanical properties and neutron irradiation resistance of these current austenitic steels cannot meet the service performance requirements for cladding of commercial fast reactors.Oxide dispersion strengthened(ODS)austenitic steel is considered to be an important candidate material for cladding application in most Generation IV reactors because of its good high-temperature mechanical properties and excellent irradiation resistance.In this study,15Ni‒15Cr ODS austenitic steel was prepared by mechanical alloying,hot isostatic pressing,and forging processes.As the reference material,15Ni‒15Cr austenitic steel without oxide addition was also prepared by the same processes.The microstructure of the sample was characterized by high-resolution transmission electron microscopy combined with a high-angle annular dark field.The average grain size of 15Ni‒15Cr ODS austenitic steels is only 0.5μm,which is smaller than that of the reference material 15Ni‒15Cr(i.e.,0.75μm).The oxide-dispersed particles distributed in 15Ni‒15Cr ODS austenitic steel are mainlyδ-Y_(4)Zr_(3)O_(12) and a small amount of Al_(2)O_(3).The average particle size of oxide-dispersed particles in 15Ni‒15Cr ODS austenitic steel is 12.8 nm,the number density is 5.5×10^(22) m^(−3),and the interparticle spacing is 26 nm.Compared with the reference material 15Ni‒15Cr,15Ni‒15Cr ODS austenitic steel exhibits higher strength, particularly at high temperature, which can be attributed to the refinement of crystal grains and the pinning effect of oxide-dispersed particles on dislocations. However, the plasticity of 15Ni‒15Cr ODS austenitic steel decreases at a high temperature of 700℃. The f

关 键 词：15Ni-15Cr 15Ni-15Cr ODS奥氏体钢 微观结构 Y-Zr-O氧化物粒子 力学性能 

分 类 号：TL341[核科学技术—核技术及应用]