All Outputs (19)

Developing neural networks to rapidly map crystallographic orientation using laser ultrasound measurements (2024)
Journal Article
Patel, R., Li, W., Smith, R. J., & Clark, M. (2025). Developing neural networks to rapidly map crystallographic orientation using laser ultrasound measurements. Scripta Materialia, 256, Article 116415. https://doi.org/10.1016/j.scriptamat.2024.116415

Rapid measurement of crystal orientation is critical in the materials discovery process as it facilitates real-time decision-making and quality control. Acoustic inspection methods rapidly characterise microstructure without the need for extensive in... Read More about Developing neural networks to rapidly map crystallographic orientation using laser ultrasound measurements.

Noncontact measurement of bolt axial force in tightening processes using scattered laser ultrasonic waves (2023)
Journal Article
Kitazawa, S., Lee, Y., & Patel, R. (2023). Noncontact measurement of bolt axial force in tightening processes using scattered laser ultrasonic waves. NDT and E International, 137, Article 102838. https://doi.org/10.1016/j.ndteint.2023.102838

This paper presents a new methodology for noncontact measurement of the axial force of bolts in their tightening processes using laser-generated ultrasound waves. This method employs ultrasound waves scattered in a bolt shaft to detect axial force ch... Read More about Noncontact measurement of bolt axial force in tightening processes using scattered laser ultrasonic waves.

Imaging Microstructure on Optically Rough Surfaces Using Spatially Resolved Acoustic Spectroscopy (2023)
Journal Article
Li, W., Dryburgh, P., Pieris, D., Patel, R., Clark, M., & Smith, R. J. (2023). Imaging Microstructure on Optically Rough Surfaces Using Spatially Resolved Acoustic Spectroscopy. Applied Sciences, 13(6), Article 3424. https://doi.org/10.3390/app13063424

The microstructure of a material defines many of its mechanical properties. Tracking the microstructure of parts during their manufacturing is needed to ensure the designed performance can be obtained, especially for additively manufactured parts. Me... Read More about Imaging Microstructure on Optically Rough Surfaces Using Spatially Resolved Acoustic Spectroscopy.

Simple method of measuring thicknesses of surface-hardened layers by laser ultrasonic technique (2021)
Journal Article
Lee, Y., Kitazawa, S., & Patel, R. (2021). Simple method of measuring thicknesses of surface-hardened layers by laser ultrasonic technique. Japanese Journal of Applied Physics, 60(7), Article 072002. https://doi.org/10.35848/1347-4065/ac030f

We proposed a simple non-contact inspection method using a laser ultrasonic technique to measure the thickness of a surface-hardened layer. This measurement is based on the dependence of a surface-wave velocity on the thickness of the hardened layers... Read More about Simple method of measuring thicknesses of surface-hardened layers by laser ultrasonic technique.

Single pixel camera methodologies for spatially resolved acoustic spectroscopy (2021)
Journal Article
Patel, R., Sharples, S. D., Clark, M., Somekh, M. G., & Li, W. (2021). Single pixel camera methodologies for spatially resolved acoustic spectroscopy. Applied Physics Letters, 118(5), Article 051102. https://doi.org/10.1063/5.0040123

Spatially resolved acoustic spectroscopy (SRAS) is a laser ultrasound technique used to determine the crystallographic orientation (i.e. microstructure) of materials through the generation and measurement of surface acoustic wave velocity on a sample... Read More about Single pixel camera methodologies for spatially resolved acoustic spectroscopy.

Non-destructive detection of machining-induced white layers through grain size and crystallographic texture-sensitive methods (2021)
Journal Article
Brown, M., Pieris, D., Wright, D., Crawforth, P., M'Saoubi, R., McGourlay, J., …Ghadbeigi, H. (2021). Non-destructive detection of machining-induced white layers through grain size and crystallographic texture-sensitive methods. Materials and Design, 200, Article 109472. https://doi.org/10.1016/j.matdes.2021.109472

Detection of machining-induced white layers is currently a destructive inspection process with a form of cross-sectional microscopy required. This paper, therefore, reports on the development of a novel non-destructive inspection method for detecting... Read More about Non-destructive detection of machining-induced white layers through grain size and crystallographic texture-sensitive methods.

Spatially resolved acoustic spectroscopy for integrity assessment in wire–arc additive manufacturing (2019)
Journal Article
Dryburgh, P., Pieris, D., Martina, F., Patel, R., Sharples, S., Li, W., …Smith, R. J. (2019). Spatially resolved acoustic spectroscopy for integrity assessment in wire–arc additive manufacturing. Additive Manufacturing, 28, 236-251. https://doi.org/10.1016/j.addma.2019.04.015

Wire-arc additive manufacturing (WAAM) is an emergent method for the production and repair of high value components. Introduction of plastic strain by inter-pass rolling has been shown to produce grain refinement and improve mechanical properties, ho... Read More about Spatially resolved acoustic spectroscopy for integrity assessment in wire–arc additive manufacturing.

Spatially Resolved Acoustic Spectroscopy Towards Online Inspection of Additive Manufacturing (2019)
Journal Article
Pieris, D., Patel, R., Dryburgh, P., Hirsch, M., Li, W., Sharples, S., …Clark, M. (2019). Spatially Resolved Acoustic Spectroscopy Towards Online Inspection of Additive Manufacturing. Insight - Non-Destructive Testing & Condition Monitoring, 61(3), 132-137. https://doi.org/10.1784/insi.2019.61.3.132

High-integrity engineering applications such as aerospace will not permit the incorporation of components containing
any structural defects. The current generation of additive manufacturing (AM) platforms yield components with relatively
high level... Read More about Spatially Resolved Acoustic Spectroscopy Towards Online Inspection of Additive Manufacturing.

Imaging material texture of as-deposited selective laser melted parts using spatially resolved acoustic spectroscopy (2018)
Journal Article
Patel, R., Hirsch, M., Dryburgh, P., Pieris, D., Achamfuo-Yeboah, S., Smith, R., …Clark, M. (2018). Imaging material texture of as-deposited selective laser melted parts using spatially resolved acoustic spectroscopy. Applied Sciences, 8(10), Article 1991. https://doi.org/10.3390/app8101991

Additive manufacturing (AM) is a production technology where material is accumulated to create a structure, often through added shaped layers. The major advantage of additive manufacturing is in creating unique and complex parts for use in areas wher... Read More about Imaging material texture of as-deposited selective laser melted parts using spatially resolved acoustic spectroscopy.

Targeted rework of powder bed fusion additive manufacturing (2018)
Presentation / Conference Contribution
Dryburgh, P., Patel, R., Catchpole-Smith, S., Hirsch, M., Parry, L., Smith, R. J., …Clare, A. T. (2018). Targeted rework of powder bed fusion additive manufacturing. In Proceedings of LPM2018 - the 19th International Symposium on Laser Precision Microfabrication (#18/030)

There is a clear industrial pull to fabricate high value components using premium high temperature aerospace materials by additive manufacturing. Inconveniently, the same materials’ properties which allow them to perform well in service render them... Read More about Targeted rework of powder bed fusion additive manufacturing.

Enhanced sensing and conversion of ultrasonic Rayleigh waves by elastic metasurfaces (2017)
Journal Article
Colombi, A., Ageeva, V., Smith, R. J., Clare, A. T., Patel, R., Clark, M., …Craster, R. V. (2017). Enhanced sensing and conversion of ultrasonic Rayleigh waves by elastic metasurfaces. Scientific Reports, 7(1), Article 6750. https://doi.org/10.1038/s41598-017-07151-6

Recent years have heralded the introduction of metasurfaces that advantageously combine the vision of sub-wavelength wave manipulation, with the design, fabrication and size advantages associated with surface excitation. An important topic within met... Read More about Enhanced sensing and conversion of ultrasonic Rayleigh waves by elastic metasurfaces.

Orientation imaging of macro-sized polysilicon grains on wafers using spatially resolved acoustic spectroscopy (2017)
Journal Article
Patel, R., Li, W., Smith, R. J., Sharples, S. D., & Clark, M. (2017). Orientation imaging of macro-sized polysilicon grains on wafers using spatially resolved acoustic spectroscopy. Scripta Materialia, 140, 67-70. https://doi.org/10.1016/j.scriptamat.2017.07.003

Due to its economical production process polysilicon, or multicrystalline silicon, is widely used to produce solar cell wafers. However, the conversion efficiencies are often lower than equivalent monocrystalline or thin film cells, with the structur... Read More about Orientation imaging of macro-sized polysilicon grains on wafers using spatially resolved acoustic spectroscopy.

Widefield two laser interferometry (2014)
Journal Article
Patel, R., Achamfuo-Yeboah, S., Light, R. A., & Clark, M. (2014). Widefield two laser interferometry. Optics Express, 22(22), https://doi.org/10.1364/OE.22.027094

A novel system has been developed that can capture the wide- field interference pattern generated by interfering two independent and incoherent laser sources. The interferograms are captured using a custom CMOS modulated light camera (MLC) which is c... Read More about Widefield two laser interferometry.

Ultrastable heterodyne interferometer system using a CMOS modulated light camera (2012)
Journal Article
Patel, R., Achamfuo-Yeboah, S., Light, R., & Clark, M. (2012). Ultrastable heterodyne interferometer system using a CMOS modulated light camera. Optics Express, 20(16), https://doi.org/10.1364/OE.20.017722

A novel ultrastable widefield interferometer is presented. This uses a modulated light camera (MLC) to capture and stabilise the interferogram in the widefield heterodyne interferometer. This system eliminates the contribution of piston phase to the... Read More about Ultrastable heterodyne interferometer system using a CMOS modulated light camera.

Widefield heterodyne interferometry using a custom CMOS modulated light camera (2011)
Journal Article
Patel, R., Achamfuo-Yeboah, S., Light, R., & Clark, M. (2011). Widefield heterodyne interferometry using a custom CMOS modulated light camera. Optics Express, 19(24), https://doi.org/10.1364/OE.19.024546

In this paper a method of taking widefield heterodyne inter- ferograms using a prototype modulated light camera is described. This custom CMOS modulated light camera (MLC) uses analogue quadrature demodulation at each pixel to output the phase and am... Read More about Widefield heterodyne interferometry using a custom CMOS modulated light camera.

Widefield ultrastable heterodyne interferometry using a custom CMOS modulated light camera (2011)
Presentation / Conference Contribution
Patel, R., Clark, M., & Achamfuo-Yeboah, S. (2011). Widefield ultrastable heterodyne interferometry using a custom CMOS modulated light camera.

A method of detecting optical heterodyne interference fringes using a custom CMOS modulated light camera array has been developed. Widefield phase images are generated using quadrature demodulation and are kept stable using a feedback system.
© 2011... Read More about Widefield ultrastable heterodyne interferometry using a custom CMOS modulated light camera.

Spatially Resolved Acoustic Spectroscopy Towards Online Inspection of Additive Manufacturing
Presentation / Conference Contribution
Milesh Pieris, D., Patel, R., Dryburgh, P., Hirsch, M., Li, W., Sharples, S. D., Smith, R. J., Clare, A. T., & Clark, M. (2018, September). Spatially Resolved Acoustic Spectroscopy Towards Online Inspection of Additive Manufacturing. Presented at NDT 2018 - 57th Annual Conference of the British Institute of Non-Destructive Testing, Nottingham, UK

High-integrity engineering applications such as aerospace will not permit the incorporation of components containing any structural defects. The current generation of additive manufacturing platforms yield components with relatively high levels of... Read More about Spatially Resolved Acoustic Spectroscopy Towards Online Inspection of Additive Manufacturing.

Spatially resolved acoustic spectroscopy (SRAS) microstructural imaging
Presentation / Conference Contribution
Clark, M., Clare, A., Dryburgh, P., Li, W., Patel, R., Pieris, D., Sharples, S., & Smith, R. (2019, May). Spatially resolved acoustic spectroscopy (SRAS) microstructural imaging. Presented at 45th Annual Review of Progress in Quanitative Nondestructive Evaluation, Vermont, USA

© 2019 Author(s). Spatially resolved acoustic spectroscopy (SRAS) is an acoustic microscopy technique that can image the microstructure and measure the crystallographic orientation of grains or crystals in the material. It works by measuring the velo... Read More about Spatially resolved acoustic spectroscopy (SRAS) microstructural imaging.

Spatially resolved acoustic spectroscopy for texture imaging in powder bed fusion nickel superalloys
Presentation / Conference Contribution
Dryburgh, P., Patel, R., Pieris, D. M., Hirsch, M., Li, W., Sharples, S. D., Smith, R. J., Clare, A. T., & Clark, M. (2019, May). Spatially resolved acoustic spectroscopy for texture imaging in powder bed fusion nickel superalloys. Presented at 45th Annual Review of Progress in Quantitative Nondestructive Evaluation, Vermont, USA

© 2019 Author(s). There is a clear industrial pull to fabricate high value components using premium high temperature aerospace materials by additive manufacturing. Inconveniently, the same material properties which allow them to perform well in servi... Read More about Spatially resolved acoustic spectroscopy for texture imaging in powder bed fusion nickel superalloys.