Neutron Through-Thickness Stress Measurements in Two-Phase Coatings with High Spatial Resolution

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Neutron Through-Thickness Stress Measurements in Two-Phase Coatings with High Spatial Resolution

V. Luzin, D. Fraser

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Neutron diffraction residual stress profiling of sprayed coatings with high spatial resolution is a difficult task. Normally, only for single-phase materials 0.1 – 0.2 mm resolution can be achieved. Stress measurements in two-phase or multi-phase coatings are an even more formidable experimental task due to the necessity of measuring all phases with lower than 100% volume fractions and the necessity to resolve the d0 problem in a more complex way than the for single-phase coating systems. The results of through-thickness residual stress profiling neutron diffraction experiments are reported on a selected two-phase, metal-metal composite coating, deposited by the cold spray technique. With both phase strains measured and complemented by additional information provided by other characterisations, the full stress state was reconstructed. Macro- and micro-stresses were separated allowing interpretation of the experimental data in terms of macro- and micro-mechanics. It also allowed us to make conclusions about the thermal mechanisms of macro- and micro-stress formation, as well as connection of these mechanisms to spraying parameters.

Keywords
Residual Stress, Coatings, Cold Spray

Published online 4/20/2018, 6 pages
Copyright © 2018 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: V. Luzin, D. Fraser, ‘Neutron Through-Thickness Stress Measurements in Two-Phase Coatings with High Spatial Resolution’, Materials Research Proceedings, Vol. 4, pp 111-116, 2018

DOI: http://dx.doi.org/10.21741/9781945291678-17

The article was published as article 17 of the book

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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