Through Thickness Residual Stress and Microstructural Mapping of AA7085-T7452 Die Forging

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Through Thickness Residual Stress and Microstructural Mapping of AA7085-T7452 Die Forging

P.S. Baburamani, K.F. Walker, P.K. Sharp , J. Niclis, A. Shekhter

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Abstract. Significant weight savings and reductions in manufacturing costs have motivated the drive towards the use of unitised structures such as large die forgings in modern aircraft. However, detrimental bulk tensile residual stresses, present in these thick forgings can impact the durability and structural integrity of the primary aerospace structure. Residual stresses can lead to distortion during component machining, and part rejection. In addition, failure to account for the residual stress effects in the fatigue crack growth characteristics of the component in design and in performance could impact the structural integrity. Therefore, there is a need to measure and analyse the residual stresses present in the forged components, and examine the residual stress-microstructure, including grain structure/flow relationship for the forging, if such a relationship could be developed. The preliminary results of this experimental program have shown a link between the measured residual stress and hardness, along with changes in the grain structures through the thickness.

Keywords
Forging, Slitting, Microstructure, Through-thickness, Residual Stress, Hardness

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: P.S. Baburamani, K.F. Walker, P.K. Sharp , J. Niclis, A. Shekhter, ‘Through Thickness Residual Stress and Microstructural Mapping of AA7085-T7452 Die Forging’, Materials Research Proceedings, Vol. 2, pp 127-132, 2017

DOI: http://dx.doi.org/10.21741/9781945291173-22

The article was published as article 22 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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