Delayed plasticity during spherical nanoindentation of an iron-chromium-aluminum alloy:Effect of ferric ion irradiation  

作　　者：Y.Zhang C.W.Li J.L.Jiang J.F.Gu H.Wang Y.D.Jia G.Wang X.G.An Q.Wang J.Lu 

机构地区：[1]Institute of Materials,Shanghai University,Shanghai 200072,China [2]School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China [3]Department of Mechanical Engineering,City University of Hong Kong,Kowloon,SAR,China [4]Science and Technology on Reactor Fuel and Materials Laboratory,Nuclear Power Institute of China,Chengdu 610041,China [5]Interdisciplinary Materials Research Center,Institute for Advanced Study,Chengdu University,Chengdu,610106,China

出　　处：《Journal of Materials Science & Technology》2023年第36期228-236,共9页材料科学技术（英文版）

基　　金：supported by the National Natural Science Foundation of China(grant Nos.52122103 and 51971207);Shenzhen-Hong Kong Science and Technology Innovation Cooper-ation Zone Shenzhen Park Project:HZQB-KCZYB-2020030.

摘　　要：Spherical nanoindentation of an iron-chromium-aluminum alloy was conducted to study the effect of ferric-ion(Fe 3+)irradiation on the time-dependent plasticity behavior in the surface layers of this alloy.It was observed that the initiation of plasticity by the appearance of displacement burst or“pop-in”event occurred after a period of waiting time in the apparent elastic regime and that Fe^(3+)irradiation at 360°C and up to∼0.5 displacements per atom could make it happen under the lower applied loads but with a reduced magnitude.Through the experimental data,an activation volume and activation energy were extracted for the delayed plasticity.The results show that Fe^(3+)-irradiation significantly reduced its acti-vation volume from∼3.05 b 3 to∼1.75 b 3(where b=Burgers vector),but slightly increased its activation energy from∼0.65 to∼0.71 eV.On the other hand,high-resolution scanning transmission electron mi-croscopy observations reveal that the irradiation at the elevated temperature created interstitial atom pair onto the(100)habit plane that can serve as the nucleation site of a100dislocation loop while elim-inating the pre-existing dislocations.Consequently,it is indicated that heterogeneous nucleation of the dislocation loop was predominant in the delayed plasticity initiation of this alloy and that the nucleation of the interstitial-type dislocation loop was involved due to Fe^(3+)-irradiation.

关 键 词：Spherical nanoindentation Delayed plasticity FeCrAl alloy Fe^(3+)-irradiation 

分 类 号：TG139[一般工业技术—材料科学与工程]