• Strobl, M.; Woracek, R.; Kardjilov, N.; Hilger, A.; Wimpory, R.; Tremsin, A.; Wilpert, T.; Schulz, C.; Manke, I,; Penumadu, D.: Time-of-flight neutron imaging for spatially resolved strain investigations based on Bragg edge transmission at a reactor source. Nuclear Instruments & Methods in Physics Research A 680 (2012), p. 27-34

10.1016/j.nima.2012.04.026

Abstract:
Energydependentneutrontransmissionimaginghasrecentlygainedattentionforthepotentialto spatiallyresolvetexture,crystallographicphaseandlatticestrain.Especiallypromisingisthetime-of- flight (TOF)approachthattakesmaximumadvantageofthenewgenerationofpulsedspallation neutronsources,suchasSNS,JSNSandESS.Inthispaper,theauthorsdemonstratethefeasibilityto efficientlyapplytheTOFapproachatacontinuoussourceinordertospatiallyresolveandquantifythe (lattice)straindistributioninaflatsteelsampleundertensileloading.Althoughtransmission-based TOF imagingforstrainmappingatapulsedsourceiswellpublished,thisworkisthefirstattemptto demonstratesuchmeasurementusingchoppersatacontinuousneutronsource.Acriticalcomponent for spatiallyresolvedTOFimagingistheavailabilityofahighspatialresolutionimagingdetector, capableoftherequiredtimeresolution.Forthehereinpresentedwork,aconventional2Dposition- sensitive 3He detectorwithaspatialresolutionof23 mm2 has beenusedforproof-of-principle measurements.Theresultsarecomparedtoconventionallatticestrainmeasurementsobtainedatan engineeringneutrondiffractometer,wherethesamemechanicalloadingsystemwasutilized.The efficiencyofthetime-of-flighttransmissionmethodisdiscussedwithrespecttoothermethods,at continuousaswellasatpulsedsources.