Residual Stress Measurement of Ti-Metal Samples by Means of XRD with Ti and Cu Radiation

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Residual Stress Measurement of Ti-Metal Samples by Means of XRD with Ti and Cu Radiation

L. Suominen, T. Rickert, S. Send

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Abstract: The use of titanium in structural components has been growing for years, especially in highly demanding applications in the aerospace industry where quality control is essential. One of the critical properties is fatigue strength, which is strongly affected by residual stresses. Residual stresses may be an unavoidable by-product of the manufacturing process or intentionally imparted through processes like shot peening. X-ray diffraction (XRD) is commonly used for residual stress measurement. Yet titanium alloys are more difficult to measure than other metals like steels and aluminium alloys. Many titanium alloys have a two-phase microstructure, one of them being hexagonal alpha titanium. Also, the commonly used Cu-radiation generates very strong fluorescence, which results in a low penetration depth. Both reduces measurement quality. Ti-radiation is much less frequently used. It benefits from very low fluorescence and a higher penetration depth. This paper compares XRD residual stress measurements using Cu- and Ti- radiation on two titanium grades: Grade 2 and Grade 5 (Ti6Al4V). The samples from both are in the rolled condition and have been shot peened. The x-ray elastic constants were determined by XRD with Cu- and Ti-radiation and samples and residual stress depth distributions were measured up to 0.5 mm depth.

Keywords
X-Ray Elastic Constant Measurement (XEC), X-Ray Diffraction (XRD), Residual Stress, Titanium Alloys, Ti-Radiation, Cu-Radiation

Published online 12/22/2016, 6 pages
Copyright © 2016 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: L. Suominen, T. Rickert, S. Send, ‘Residual Stress Measurement of Ti-Metal Samples by Means of XRD with Ti and Cu Radiation’, Materials Research Proceedings, Vol. 2, pp 61-66, 2017

DOI: http://dx.doi.org/10.21741/9781945291173-11

The article was published as article 11 of the book Residual Stresses 2016

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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