Insight - Non-Destructive Testing and Condition Monitoring · 2005 · 45 citations · 2 references
EngineeringMaterials EngineeringMaterials ScienceInstrumentationMaterials CharacterizationMetrologyFiber OpticsIndustrial MetrologyInterferometryOptical FibersOptical InstrumentationOptical MetrologyCrater DetectionInterferometric MeasurementLaser-induced BreakdownLaser-induced Breakdown SpectroscopyLow-coherence InterferometryOptical Coherence SpectroscopyRheometer MeasurementsWear Mechanisms
Low‑coherence interferometry (LCI) is a micron‑range optical metrology technique that, using fibre‑linked probes, offers rugged, miniaturised measurement capability suitable for industrial environments and has also been employed in LIBS for depth‑resolved compositional analysis. The study presents several industrial applications of LCI developed at IMI, including an elongational rheometer, wear‑damage characterization, and integration with laser‑induced breakdown spectroscopy. LCI is incorporated into an elongational rheometer that stretches polymer samples up to 350 °C, into a wear‑test setup that quantifies volume loss, and into a LIBS instrument to measure crater depth between laser shots, requiring high depth resolution but relatively coarse transverse resolution. LCI successfully monitors sample thickness and accurately measures crater depth in LIBS, confirming its effectiveness for these industrial metrology tasks.
Low-coherence interferometry (LCI) is an optical technique that may be used for industrial surface metrology with accuracy in the micron range. An instrument made with optical fibres is rugged enough to be used in industrial environments and the fibre-linked optical probe may be miniaturised for accessing tight locations. Among industrial applications developed at IMI, several cases for which LCI has been particularly useful, such as an elongational rheometer (RME), characterisation of wear damages on coating and laser-induced breakdown spectroscopy (LIBS), will be presented. The RME is an instrument in which a polymer sample is stretched in a controlled temperature furnace at up to 350°C. LCI has been used for monitoring the thickness of the samples. Wear damage is quantified by the volume loss after a wear test. It requires a high depth resolution (axis perpendicular to the surface) but a relatively coarse transverse resolution. The LIBS is a technique that has been used for analysing the chemical composition of materials as a function of depth. LCI has been integrated to a LIBS instrument for measuring accurately the crater depth between each laser shot.
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