AComparisonoftheElectronandIonIrradiationEffectsonthe：在电子和离子束辐照效应的比较文课件

1、OutlineOrdering chemical, magnetic, & electric Evolution of Ordering Competing superlattices in Ni4Mo alloy Influence of radiation on order disorder Order evolution - under electron irradiation - under heavy ion irradiationComparison of electron and ion irradiation results Conclusions第1页，共44页。Orderi

2、ng Chemical, ferromagnetic, ferroelectric Chemical OrderingFerromagneticFerroelectric OrderingEmptylatticeAtoms A & BElectric/magneticmoments第2页，共44页。OutlineOrdering chemical, magnetic, & electric Evolution of Ordering Competing superlattices in Ni4Mo alloy Influence of radiation on order disorder O

3、rder evolution - under electron irradiation - under heavy ion irradiationComparison of electron and ion irradiation results Conclusions第3页，共44页。Evolution of orderNucleation and GrowthContinuous OrderingOrder evolution could be either first or second order第4页，共44页。Evolution of Ordering: Discrete Mode

4、 (Nucleation & Growth)NucleationDisorderedMatrix第5页，共44页。Evolution of Ordering Static Concentration WavesSingle Variant K vector B2 Ordering3 variants K vector L12 ordering第6页，共44页。Continuous OrderingAmplification of concentration wave with time第7页，共44页。First & second order transitions: Thermodynami

5、c viewpointnth order transformation:FECpTemperature First Order Second order第8页，共44页。Energy barrierNucleation & growthFirst & second order transitions: Landau PlotsFirst Order(Discrete)Second order(Continuous)第9页，共44页。OutlineOrdering chemical, magnetic, & electric Evolution of Ordering Competing sup

6、erlattices in Ni4Mo alloy Influence of radiation on order disorder Order evolution - under electron irradiation - under heavy ion irradiationComparison of electron and ion irradiation results Conclusions第10页，共44页。Ordered States in Ni4 Mo* Above 1140 K alloy is in SRO state* Below 1140 K alloy is in

7、LRO state* By conventional solutionising and quenching treatment alloy can not be produced in the completely disordered state (CDO)* LRO and SRO are two different states第11页，共44页。Description of LRO and SRO structures001 ProjectionLRO stateSRO statep = 0,1,2,3 for modulationp = 0,1,2,3, 4 for 1/5 mod

8、ulation第12页，共44页。Concentration wave packets MicrodomainsStructural description of OrderingIsostructural microdomainsSRO LRO 1/5 Different from SRO intensifying to become LRO Multiple microdomainsDisordered matrix第13页，共44页。OutlineOrdering chemical, magnetic, & electric Evolution of Ordering Competing

9、 superlattices in Ni4Mo alloy Influence of radiation on order disorder Order evolution - under electron irradiation - under heavy ion irradiationComparison of electron and ion irradiation results Conclusions第14页，共44页。OutlineOrdering chemical, magnetic, & electric Evolution of Ordering Competing supe

10、rlattices in Ni4Mo alloy Influence of radiation on order disorder Order evolution - under electron irradiation - under heavy ion irradiationComparison of electron and ion irradiation results Conclusions第15页，共44页。Electron Irradiation Results1 MeV electronsDose rate = 10-3 dpa/s第16页，共44页。Evolution of

11、Order in Ni4Mo under electron Irradiation170 K473 KDisordering of LRO statePersistence of 1 0 order (SRO) in initial SRO state第17页，共44页。Evolution of Order in Ni4Mo under electron IrradiationDamage rate: 103 dpa/s & 1/5 diffraction spotsremain linked during evolutionary stagesS Banerjee, K Urban, M.

12、WilkensActa Met., 32 (1984) 299 第18页，共44页。Ordering Mechanisms Maps for Ni4Mo under e- irradiationA: Destruction of LROB: No significant change of order for S=0, S=1 C: Continuous ordering by decay of waves & simultaneous amplification of LROD: Initially as in region C, after disappear, D1a domains n

13、ucleate & growE: Nucleation & growth of D1aF: Destruction of G: order decays at T 550 KH: growsI: Destruction of & transition to LROS Banerjee, K Urban, M. Wilkens Acta Met., 32 (1984) 299 No LRO state below 450 KNo SRO State below 200 K第19页，共44页。Ordering & Disordering JumpsAsymmetric energy barrier

14、 for vacancy-atom Interchange in ordered alloy第20页，共44页。Order-parameter vs. temperature plots equilibrium condition- steady state condition under irradiationComparison between theory & experimentequilibriumUnder irradiationS. Banerjee, K. Urban, Phys. Stat. Sol., 81, (1984) 145第21页，共44页。OutlineOrder

15、ing chemical, magnetic, & electric Evolution of Ordering Competing superlattices in Ni4Mo alloy Influence of radiation on order disorder Order evolution - under electron irradiation - under heavy ion irradiationComparison of electron and ion irradiation results Conclusions第22页，共44页。Ion Irradiation R

16、esults300 keV Ni+ ionsDose rate = 10-3 dpa/s第23页，共44页。Displacement cascades produced by 60 keV Au+ ions in ordered Ni4 Mo (D1a)Black-white contrast From Dislocation loops (g = 200)Disordered zones images withSuperlattice reflection (g = 1/5 M. Sundararaman, S. Banerjee, H. Wollenberger, Acta Met., 4

17、3, (2019) 107第24页，共44页。Evolution of Order in Ni4Mo under ion IrradiationGradual decay of SRO and LRO states to CDO state第25页，共44页。Evolution of Order in Ni4Mo under ion IrradiationDecay of LRO and gradual development of SRO intensity300 keV Ni+ ; Irradiation temperature - 600 KDose rate - 10-3 dpa/s第

18、26页，共44页。Evolution of Order in Ni4Mo under ion IrradiationDevelopment of SRO in the initially SRO and LRO specimensi-SROi-LRO第27页，共44页。Evolution of order in Ni4Mo under ion IrradiationFinal steady states at different irradiation temperaturesi-SROi-LRO第28页，共44页。Loop size greater than 10 nmDislocation

19、 loops in irradiated Ni4Mo;T = 900 CFrank loops第29页，共44页。Steady state structures in Ni4Mo under ion irradiationInitial state Domains Transitions A disappears B decays C grows D experimentally inaccessible 1/5 E 1/5 decays & grows F 1/5 persists 第30页，共44页。Cascade dynamicsDisplacement cascade 10-13 sT

20、hermal spike 10-11 sFinal order decided by disordering and reordering within thermal spikeQuenching of thermal spike- Amorphous- Complete disorder- Partial OrderNet vacancy concentration inside the cascadeBy diffusion to periphery form loops around cascadeSubstrate / sample temperature / thermal con

21、ductivity第31页，共44页。Comparison of electron and ion irradiation results第32页，共44页。Comparison between electron & ion irradiationSteady state structures developed during e- and ion irradiationStochastic potential for maximum order versus TExperimentTheoryLower bound for LRO stability matches with experim

22、ent for e- irradiation第33页，共44页。ConclusionsDistinct stability regimes for the CDO, the SRO and the LRO states could be obtained for electron and ion irradiationCascade effect decreases the temperature range of stability of LRO state while increases the temperature range of stability of SRO stateFor

23、electron irradiation, mixed state (SRO and LRO) can co-exist between 450 K and 800 K. No mixed state exist for ion irradiationLow temperature for stability of LRO calculated by Kinetic and stochastic models match with experimental observation for electron irradiation第34页，共44页。AcknowledgmentsDr. U.D.

24、 Kulkarni, BARCProf. K. Urban, KFA, JlichProf. H. Wollenberger, HMI, Berlin第35页，共44页。Thank you第36页，共44页。Reaction kinetics model第37页，共44页。Kinetics: Rate of Change of point-defect concentrations (Vacancy, V, & Interstitial, I) Production transfer transferAnnihilation at sinksRecombination, : sublattic

25、e sitesS. Banerjee, K. Urban, Phys. Stat. Sol., 81, (1984) 145第38页，共44页。Radiation Effects in SolidsRadiation Enhanced / Induced SegregationRadiation Enhanced / Induced DiffusionRadiation Enhanced / Induced Phase Transformation-Generation of new phases-vacancy orderedRadiation Enhanced / Induced Redistribution第39页，共44页。Irradiation induced processesDisordering temperature independentReordering - temperature dependentNet effect decides the final structure第40页，共44页。Radiation Induced Disorderinge-ve-IvvIIIonReplacement CollisonRandomRecombinationDisplacementCascadeM