1. Dept of Materials Engineering l Use of a Virtual Laboratory to plan, execute and analyse Neutron Strain Scanning experiments. John A James 1, Javier R Santisteban 1, Mark R Daymond 2 and Lyndon Edwards 1 1. Dept of Materials Engineering, Open University, Milton Keynes, UK 2. ISIS Facility, Rutherford Appleton Laboratory, Chilton, Oxon, UK

2. Dept of Materials Engineering l Overview Brief background on stress measurements with ENGINX. SScanSS Software demonstration.

3. Dept of Materials Engineering l Diffraction-based Stress Measurement Strain The Atomic Strain Gauge

4. Dept of Materials Engineering l Time of Flight (TOF). Spallation source. Range of energies  in each pulse. Each detector contains a complete spectra. Detectors focussed to produce a single spectra. Lattice cell size obtained via a Rietveld refinement.

5. Dept of Materials Engineering l The Gauge volume Neutron Strain Scanning

6. Dept of Materials Engineering l Complete components. Samples of Welds and fastenings. New technologies and new materials. Deep measurements. Area scanning. Dynamic stress fields; variable stress or variable temperature loading. Often measurements required deep in a sample of large size or complex geometry positioned with high accuracy Typical samples and measurements

7. Dept of Materials Engineering l Cold Expanded Holes The primary source of aircraft fatigue is at joints. Cold expansion increases joint durability. Quantification of the benefits of cold expansion requires accurate reliable residual stress estimation.

8. Dept of Materials Engineering l Previous samples and components

9. Dept of Materials Engineering l Increasingly important technique in engineering => pressure on beam time Of interest to commercial users (‘value for money’) => pressure on beam time Experience gained on ENGIN prompted new design. New machine ENGIN-X currently being commissioned. ENGIN ENGIN-X

10. Dept of Materials Engineering l Increase in performance gives Smaller gauge volumes Faster measurements Deeper measurements Real time measurements ENGIN-X has 10 times the performance of ENGIN.

11. Dept of Materials Engineering l Defining measurement points and orientations. Calculating measurement times. Moving the positioner to execute the measurement plan. Modifying measurement plan. Previously manual methods. Areas of difficulty with measurement routine.

12. Dept of Materials Engineering l Integrated Software support to maximise “Information output per unit of beam time” Computer aided measurement plans. Automated execution. Fast data analysis to permit real time modification of measurement plan. Powerful visualisation options. Accessible to non-neutron specialists.

13. Dept of Materials Engineering l

14. lHowever…….. Problem; Speed and accuracy of ENGINX hardware compromised by supporting methods. Solution; Software support to MAXIMISE “Scientific information output per unit of beam time” ?

15. Dept of Materials Engineering l Strain Scanning Simulation Software SScannSS

16. Dept of Materials Engineering l The Virtual sample.

17. Dept of Materials Engineering l Fiducial points and planes. Minimum of three non-linear fiducial points; used for locating sample within virtual lab. Reference planes eg. Welds may be specified.

18. Dept of Materials Engineering l MEASUREMENT POINTS

19. Dept of Materials Engineering l POSITIONING

20. Dept of Materials Engineering l THEODOLITE TOOL

21. Dept of Materials Engineering l RUN SIMULATION

22. Dept of Materials Engineering l DATA REDUCTION.

23. Dept of Materials Engineering l VISUALISATION Simple 2d and 3d plots – other options to be added.

24. Dept of Materials Engineering l Possible extensions Possible extensions.