Improvement in irradiation resistance of FeCu alloy by pre-deformation through introduction of dense point defect sinks  

作　　者：Hao Wu Qiu-Lin Li Ben Xu Hai-Long Liu Guo-Gang Shu Wei Liu 

机构地区：[1]Graduate School at Shenzhen,Tsinghua University,Shenzhen 518055,China [2]School of Materials Science and Engineering,Tsinghua University,Beijing 100084,China [3]State Key Laboratory of Nuclear Power Safety Monitoring Technology and Equipment,China Nuclear Power Engineering Co.Ltd,Shenzhen 518172,China

出　　处：《Rare Metals》2021年第4期885-896,共12页稀有金属（英文版）

基　　金：financially supported by the National Key Research and Development Program(Nos.2016YFB0700401 and 2017YFB0305304);the Basic Research and Development Program(No.JCYJ20170307153239266)。

摘　　要：The irradiation resistance of pre-deformed FeCu alloy was studied using a 3 MeV Fe ion irradiation experiment at room temperature in comparison with that of the as-received sample.Nanoindentation and atom probe tomography(APT) were used to characterize the mechanical properties and solute distribution.The stress-strain curve obtained by nanoindentation shows that the yield strength(σ0.2) of the pre-deformed sample is unexpectedly reduced with an increase in the irradiation dose to five displacements per atom(dpa).We suggest that it results both from the decrease in the dislocation density and the suppression of defects during irradiation.APT shows that the nucleation of the Cu cluster is suppressed;however,its growth is promoted in the pre-deformed sample,resulting in the formation of sparse and coarse clusters at 1 dpa irradiation.These coarse Cu clusters were then unexpectedly refined to finer grains with an increase in the irradiation dose to 5 dpa.Theoretically,the improvement in the resistance to irradiation in the pre-deformed sample is attributed to the dense point-defect sinks,that is,the dislocations and grain boundaries introduced by pre-deformation.In addition,the contributions of the dislocations and grain boundaries to the sink strength are estimated for both the as-received and pre-deformed samples.The results indicate that dislocations,rather than grain boundaries,play a major role after deformation.

关 键 词：Reactor pressure vessel Irradiation damage PRE-DEFORMATION Dislocation density Cu-rich clusters 

分 类 号：TG132[一般工业技术—材料科学与工程] TM623[金属学及工艺—合金]