UK Research Centre in NDE

Lead Research Organisation: Imperial College London
Department Name: Mechanical Engineering

Abstract

The prime aim of the Centre is to do world-class research in NDE and related fields. The Centre is a collaboration between six universities and 14 (in 07-08)large, end-user companies plus a number of smaller, associate members. The membership includes expertise in mechanical and electronic engineering, physics and materials, so recognising the interdisciplinary nature of NDE. The Centre will have a wide portfolio of activities from longer term, higher risk adventurous research, through medium term application research and development to short term practical projects and technology transfer activities with SMEs and other exploiters of new products. The EPSRC funds that are the main subject of this proposal will support longer term, adventurous research in three key priority areas: defect sizing to improve structural integrity assessments, permanently installed monitoring systems to reduce the down-time associated with inspection, and exploiting advances made in other areas to introduce innovative technology to improve the quality of NDE instrumentation. Over 50% of the cost of the research will be met by industrial contributions. The purpose of all the research, whether shorter or longer term, will be to benefit the nation in terms of quality of life, through improved safety, environmental protection and economic security. The Centre will do this by assisting UK companies to improve (a) their competitiveness and (b) their ability to meet the public's requirements for safe and secure operation.
 
Description The UK Research Centre in Non-destructive Evaluation (RCNDE) is a collaboration between EPSRC, universities and industry to perform world-class research in NDE and related fields. The Centre has a wide portfolio of activities from longer term, higher risk adventurous research, through medium term application research and development to short term practical projects and technology transfer activities with SMEs and other exploiters of new products. EPSRC funds support the longer term, adventurous research while industry funds support the full range of research. A wide range of research outcomes have been delivered, information disseminated to the community and technology transfer actions put in place. Short summaries of the key EPSRC funded 'core' research outcomes are summarised here together with key references:

1. Next-generation ultrasonic arrays (University of Bristol).
Research to develop array-based ultrasonic inspection techniques for difficult applications - including difficult defect morphologies, materials or inspection geometries. Outputs include:
• Development of generic modelling tools for simulating array data from arbitrarily shaped defects.
• Development of 3 new defect sizing strategies for different defect size regimes.
• Experimental demonstration of sizing and imaging techniques on real defects and components.
• Quantification of the effect of crack roughness on detectability, and optimisation of array imaging in materials with strong material back-scatter.
• Delivery of a freely available, comprehensive software platform to enable users to investigate and optimise imaging algorithms and facilitate technology transfer.
Key references:
[a] Velichko, A., Wilcox, P., J. Acoust. Soc. Am., Vol. 128, pp.1004-1014, 2010.
[b] Zhang, J., Drinkwater, B., Wilcox, P., J. NDE, Vol. 29, pp. 222-232, 2010.
[c] Wilcox, P., Review Prog. QNDE, Vol. 30, pp. 890-897, 2011.
[d] Zhang, J., Drinkwater, B., Wilcox, P., IEEE Trans. Ultr. Ferroelect. Freq. Contr., V. 59, pp. 939-948, 2012.
[e] Zhang, J., Drinkwater, B., Wilcox, P., IEEE Trans. Ultr. Ferroelect. Freq. Contr., V. 60, pp.1732-1745, 2013.

2. Super resolution imaging in NDE (Imperial College)
Research based on new inverse scattering techniques applied to modern array technology, to improve current ultrasound NDE detection and characterisation techniques:
• Implementation of a near real-time single-frequency super-resolution algorithm.
• Understanding the limitations of using existing quantitative algorithms with standard linear arrays.
• Improved quantitative imaging algorithms to better deal with the limited view problem.
• Demonstration of the new imaging algorithms using simulations and experimental data.
• Experimental demonstration of broadband super resolution on notches in elastic solids.
Key references:
[a] Simonetti, F., Fleming, M., Marengo, EA., J. Opt. Soc. Am A, 25: 292-303, 2008.
[b] Hutt, T. and Simonetti, F., J. Appl. Phys., Vol. 108, 064909, 2010.
[c] Huthwaite, P., and Simonetti, F., J. Acoust. Soc. Am., 103, 1722-34, 2011.
[d] Huthwaite, P., Zwiebel, A., Simonetti, F., IEEE Trans UFFC, 60, 603-613, 2012.

3. Laser ultrasonics for detection of damage precursors (University of Nottingham).
Assessment and development of 'nonlinear' ultrasonic techniques for the early detection of damage precursors, prior to the formation of cracks and dislocations measurable by conventional linear ultrasonics. Outputs include:
• Development of a new system capable of repeatedly imaging highly accurate surface acoustic wave acoustoelastic measurements.
• Increased understanding of the relationship between acoustoelasticity (material nonlinearity), fatigue (damage precursor), and microstructure.
• A method for determining the porosity of fibre reinforced Ti-MMCs using massive linear velocity shift, understanding of the cause/mechanisms, and backed up by FEM.
Key references:
[a] Ellwood, R., Stratoudaki, T., Sharples, S., Clark, M., and Somekh,M., 2014., J Acoust Soc Am (Accepted for publication 21 Jan 2014).
[b] Chen, X., Sharples, S.D., Clark, M., and Wright, D., J Acoust Soc Am Vol 133(2), 760-9, 2013.
[c] Stratoudaki, T., Ellwood, R., Sharples, S., Clark, M., Somekh, M.G., Collison, I.J., J Acoust Soc Am, Vol 129(4), 1721-1728, 2011.
[d] Ellwood R., Stratoudaki T., Sharples S.D., Clark M., and Somekh M.G., J Phys: Conf. Series. 278(1), 2011.

4. Advanced thermography (University of Bath)
Research programme aimed at identifying and investigating a range of novel approaches to enhance thermography techniques and to improve the basic understanding and physical basis of the method. Results have included:
• Development of an analytical equation that accurately represents the behaviour of 2D defects (or rotationally symmetric 3D defects) as an extension to the wellknown equation for 1D heat flow in a semiinfinite sample with a Dirac delta heat input.
• Development and validation of a Finite Difference Equation (FDE) code based on the analytical equation which is now being used as the basis of software to provide advice to user on thermography technique set up and performance.
• Improved thermography techniques including long pulse thermography, defocused laser excitation and use of new high power LED heat sources.
Key references:
[a] Chatterjee, K., Tuli, S., Pickering, S. G. and Almond, D. P., NDT & E Int, 44 (7), pp. 655-667, 2011.
[b] Almond, D. P., Pickering, S. G., J App Phys, 111 (9), 2012.
[c] Pickering, S.G., Chatterjee, K., Almond, D.P. and Tuli, S., NDT & E Int, 58, pp. 72-77, 2013.
[d] D.P.Almond & S.G.Pickering., Materials Evaluation, 72, no.1, 83-90, 2014.
5. New approaches to NDE with micromachined transducers (University of Warwick).
This project has successfully generated the basis for exploitation of the rapid and low cost Micro-Stereo Lithography (MSL) technique for future NDE transducer developments. Development and characterisation of a range of transducers has included:
• Electrostatic ultrasonic devices which have promise for structural health monitoring or acoustic emission monitoring.
• Electromagnetic Acoustic Transducer (EMAT) coils with different geometries to generate ultrasonic beams at various angles and to enable use as detectors for laser-generated ultrasound.
• Miniature and flexible eddy current arrays for inspection of components with difficult or varying geometries.
Key references:
[a] Ho, KS., Bradley, RJ., Billson, DR., and Hutchins, DA., Ultrasonics. 48, 1-5, 2008.
[b] Yin, X., Hutchins, DA., Diamond, GG., and Purnell, P., Cement and Concrete Res., Vol.40,1734-1743 2010.
[c] Dixon, SM., Burrows, SE., and Fan. Y., Ultrasonics, Vol 51, 7-16, 2011.
[d] Hutchins, DA., Billson, DR., Bradley, RJ., and Ho, KS., Ultrasonics Vol.51, 870-877, 2011.
[e] Cheneler, D., Bowen, J., Leigh, SJ., Purssell, CP., Billson,DR., Hutchins, DA., Ward, CL., Ultramicroscopy 1, 1214-1223, 2011.

6. Future electronic platforms for ultrasonic NDE (University of Nottingham)
Research project to establish the feasibility of high density electronic system integration for highly compact ultrasonic phased array instrumentation:
• Design constraints have been established in relation to signal levels, noise performance, device dimensions and cost, with particular emphasis on optimisation of data acquisition timing.
• Development of an extremely compact electronic design for a 128-channel system, achieved by a fundamental shift away from conventional high voltage/ high current pulse excitation.
• Development and commercialisation of a single channel prototype instrument.
• A prototype 128-channel system is being manufactured with all system electronics miniaturised for incorporation into the array transducer casing for greatly improved portability and extension of array inspection in difficult access NDE applications.
Key references:
[a] Challis, RE., and Ivchenko, V.G., Meas. Sci. Technol, Vol. 22, pp. 1-12, 2011.
[b] Challis, RE., and Ivchenko, VG. Prepared, delaying publication to protect IP in the short term. Target journals Meas. Sci. Technol, IEEE Trans UFFC.

7. Permanently installed monitoring of creep damage (Imperial College).
Development of a quasi-dc potential drop measurement technique for monitoring the progress of creep:
• Successful development of a method which effectively provides a high temperature strain gauge with a gauge factor of around 5-6 in the early stages of creep. In the later stages the gauge factor increases to around 10.
• Production of a robust measurement system that gives excellent results in the lab, is suitable for limited site trials and provides a potentially robust monitoring method.
• A deployable probe has been constructed and it has been confirmed that the changes due to voiding late in the creep life of a 2.25% Cr - 1% Mo ferritic steel specimen are less than 1%; this order of magnitude has been confirmed by an analytical model;
• The changes due to voiding may be larger in the vicinity of welds where the defects are concentrated in the plane of the fusion face; this is being investigated in a follow-on project.
Key references:
[a] Sposito, G., Ward, C., Cawley, P., Nagy, P. and Scruby, C., NDT&E International, Vol 43, pp555-567, 2010.
[b] Madhi, E., Sposito, G., Davies, CM., Cawley, P. and Nagy, PB., Review of Progress in Quantitative NDE, Vol 30, DO Thompson and DE Chimenti (eds), American Institute of Physics, pp1631-1638, 2011.
[c] Prajapati, S., Nagy, P.B. and Cawley, P. NDT&E International, Vol 47, pp56-65, 2012.
[d] Prajapati, S., Nagy, P. B., and Cawley, P., Review of Progress in Quantitative NDE, Vol 31, DO Thompson and DE Chimenti (eds), American Institute of Physics, pp417-424, 2012.

8. Nonlinear material inspection (University of Bristol).
Programme to develop a robust nonlinear ultrasonic inspection technique, given that equipment often induces nonlinearity and the nonlinear signals are themselves typically several orders of magnitude smaller than the linear signals:
• The work has shown how harmonic generation methods need to be corrected to produce a measurement suitable for comparison across multiple specimens. In addition the effects of experimental variability were studied. This work is vital to ensure that measurements made at different distances and with different specimens can be compared.
• The research has shown the potential of the noncollinear technique, which relies on mixing of two waves to generate a third wave due to material nonlinearity and in principle can be used to detect changes in material state.
Key references:
[a] Croxford, A., Wilcox, P., Drinkwater, B., Nagy, P., J. Acoust. Soc. Am., Vol. 126, pp. EL117-EL122, 2009.
[b] Liu, S., Croxford, A., Neild, S., IEEE Trans. Ultr. Ferroelectr. Freq. Contr., Vol. 58, pp. 1442-1451, 2011.
[c] Liu, S., Best, S., Neild, S., Croxford, A., NDT & E Int., Vol. 48, pp. 46-53, 2012.
[d] Best, S., Croxford, A., Neild, S., Ultrasonics, Vol. 54, pp. 442-450, 2014.

9. Reconfigurable systems for automated & remote NDE (University of Strathclyde).
Research on novel robot traction and positioning, sensor integration and data fusion has successfully developed a number of small autonomous, wireless robotic devices with a range of inspection payloads geared for NDE applications involving restricted access or large areas. Outcomes include:
• Significant progress in characterising different positional sensors and algorithms for accurate robot positioning.
• Evaluation and enhancement of new sensors including air-coupled ultrasonic inspection, focusing on the creation of a synthetic ultrasonic array using a single robot with pulse-echo transducers, and a new 'whisker' sensor for surface characterisation
• Delivery of a demonstrator system (TRL 4) that can perform automated Magnetic Flux Leakage and visual inspection. Results from each dataset can be fused into a single composite result and presented clearly to the operator.
Key references:
[a] Macleod CN, Pierce SG, Sullivan JC, Pipe A, Dobie G and Summan R., Accepted for publication in IEEE Sensors Journal, 2014.
[b] Dobie, G., Pierce, SG., and Hayward, G., NDT & E International, Volume 58, pp 10-17, September 2013.
[c] Dobie G., Summan, R., MacLeod, C., Pierce, SG., NDT&E International, Volume 57, pp 17-25, July, 2013.
[d] Jackson, JC., Summan, R., Dobie, G., Whiteley, S., Pierce, G., Hayward, G., IEEE Trans. Ultrason. Ferroelectr. Freq. Contr, Vol 60 (2), pp 343-355, 2013.
[e] Dobie, G., Summan, R., Pierce, SG., Galbraith, W., Hayward, G., IEEE Sensors Jour Vol 11 (10), pp 2458-2468, 2011.
Exploitation Route The ultimate objective is for the research to lead to new and improved methods for inspection of plant and products by industry. The research has already been taken forward - both by universities with follow-on development programmes and directly by industry. As RCNDE is jointly funded by industrial end users, and also has more than 30 associate members from the supply chain, industry is well placed to take the research forward. Exploitation routes have already included:
•Open access - where universities make the results of research freely available and will often provide support to exploiting organisations
•End user adoption - where end user members take up the technology for use in their own plant and facilities
•Licensing - where commercial terms are agreed with one or more organisations to supply products or services to the market
•Spin-out - where universities establish companies directly to supply products or services.
Sectors Aerospace, Defence and Marine,Chemicals,Energy,Manufacturing, including Industrial Biotechology,Transport
URL http://www.rcnde.ac.uk
 
Description The research is aimed at providing new and improved non-destructive testing capabilities to support industry across several market sectors ranging from advanced manufacturing to companies managing major plant and infrastructure. The work has developed a pipeline of more than 50 potentially exploitable products at different stages of development - ranging from new techniques, sensors and systems to imaging algorithms and inspection modelling. Some outcomes have already been used directly through in-house implementation by end users and some incorporated into commercial systems offered through the supply chain (including spin-outs). RCNDE continues to run annual technology transfer events that are promoting the technology.
First Year Of Impact 2012
Sector Aerospace, Defence and Marine,Energy,Manufacturing, including Industrial Biotechology,Transport
Impact Types Economic
 
Description UK Research Centre in NDE 2014-2020
Amount £5,210,000 (GBP)
Funding ID EP/L022125/1 
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 04/2014 
End 03/2020