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Automatic fiber placement (AFP) is an innovative method for fabricating monolithic large-scale composite structures, such as the big and long barrels that can be assembled to make the fuselage of an airplane. Laser-ultrasonics and laser tapping, which use lasers for generation and detection of ultrasound, are established inspection techniques that are very efficient for detecting flaws (delaminations, disbonds) in complex shape composite structures. A laser-ultrasonic system with a configuration well adapted for the inspection of these big barrel structures was designed, built and installed at the National Research Council of Canada facility, located at Mirabel, Qc, adjacent to composite manufacturing operations. The laser-ultrasonic system is mounted on a long cantilever structure that is inserted into the fuselage. The probing head includes a rotating mirror assembly allowing 360° and one meter wide or more scanning of the whole internal wall of the barrel. The system can also inspect the external wall, when the barrel is mounted on carriage allowing rotation around its axis, as well as various smaller complex shape parts. This inspection system can be operated in both laser-ultrasonic and laser-tapping modes, the latter being particularly useful for honeycombs. A detailed description of the system is presented., 26th Annual Technical Conference of the American Society for Composites 2011 and the 2nd Joint US-Canada Conference on Composites, 26 September 2011 through 28 September 2011, Montreal, QC

Twelfth International Conference on Textures of Materials, 9-13 August 1999, Montreal Canada

Laser-ultrasonics is used as a non-contact technique to determine reliably and rapidly the crystallographic texture, the average plastic strain ratio, and the thickness of sheet metal on the production line. With laser-ultrasonics, a short laser pulse is used to generate a wideband pulse of ultrasound and a laser interferometer is used for detection. In this paper, a large number of echoes are collected and analyzed together to measure the natural resonance frequencies in the thickness of the sheet. From these frequencies, two texture coefficients, W400 and W420 are calculated, as well as a highly accurate measurement of the sheet thickness. Using these texture coefficients and well-known relationships, the average and planar variation of the plastic strain ratio, respectively 'r' and Δr, can be evaluated. Both parameters are indications of the formability of metals sheets. Measurements on 1 mm thick, ultra-low-carbon steel sheets at LTV Steel Company have shown the following measurement accuracies: 'r' to within ±0.04, Δr to within ±0.1, thickness to better than ± 1 μm., International Symposium on Advanced sensors for metals processing, 22-26 August 1999, Quebec City, Canada

International audience; In this paper, we describe a system that has been developed, which comprises a high power short pulse laser for ultrasound generation, a long pulse receiving laser for ultrasound detection, a demodulating interferometer, an optical scanner and a data analysis system for data acquisition and processing. Following many tests performed on composite parts in the laboratory, we present demonstration tests performed with this system on a CF-18 aircraft in a maintenance hangar. These tests show that the technology is now sufficiently advanced to be readily applicable to the inspection of detached components following manufacturing and for the in-service inspection of aircrafts. Recents developments of quantitative models which describe the generation of ultrasound in composite materials are outlined, as well as on-going improvements to the detection sensor.

International audience; In this paper, we describe a laser-ultrasonics system that comprises a high power short pulse laser for ultrasound generation by thermoelastic effect, a long pulse receiving laser for detecting ultrasound off the surface, an optical scanner and a data analysis system for data acquisition and processing. The application of the technique to the inspection of large area panels and contoured specimens is illustrated by two examples. Several recent developments aimed at understanding more quantitatively the generation aspect in composite materials and at modeling the whole generation and flaw detection process are also presented. The technology appears quite suitable and sufficiently advanced to be applicable to the inspection of detached components following manufacturing and for the in-service inspection of aircraft.

Quantitative mineralogy is an established discipline in the geosciences and is aimed at providing mineral grade and texture information for geological and mineral processing applications. The two core technologies underpinning Quantitative Mineralogical Analysis (QMA) are Scanning Electron Microscopy (SEM) in combination with Energy-dispersive X-ray Spectroscopy (EDS). Technologies such as QEMSCAN and MLA are now routinely used to optimise the performance of large-scale mineral processing plants in the base and precious metal sectors. One of the major disadvantages of the QMA methods used today is extensive sample preparation requirements which make application of this technique to real-time mineralogical characterization not feasible. A breakthrough has been achieved by the National Research Council Canada in collaboration with CRC ORE by developing a novel Laser Induced Breakdown Spectroscopy (LIBS) based technology capable of real-time mineralogical characterization of process streams without sample preparation. The potential applications of this technology include, but not limited to, in-pit muck piles, underground draw points, cross-belt analysis as well as slurries. This paper describes the development of the LIBS-based technology from a proof-of-concept (TRL2) to the construction of a prototype sensor and its validation in a simulated environment (TRL5). Future work is being planned to test and further validate the LIBS sensor on a mine-site which will progress the technology to its next readiness level TRL6)., Australasian Institute of Mining and Metallurgy (AusIMM) Preconcentration Digital Conference, 10-11, 17-18 November 2020, Online