Analysis of Residual Stress State in Deep-Rolled HT-Bolts

Analysis of Residual Stress State in Deep-Rolled HT-Bolts

J. Unglaub, J. Hensel, R. Wimpory, T. Nitschke-Pagel, K. Dilger, K. Thiele

Abstract. Results of residual stress measurements of HT-bolts gained by neutron diffraction at HZB will be presented. The in-depth residual stress of different conditions of “rolled-before heat-treatment and galvanized” M24 HT-bolts made from 33MnCrB5-2 will be shown: As-manufactured, pre-stressed and fatigue loaded. Additionally, results of an unloaded, “rolled-after heat-treatment and hot-dipped” galvanized M36 HT-bolt will be presented. It will be shown that the manufacturing sequence “rolled-before heat-treatment and galvanized” can develop compressive residual stresses due to heat-treatment close to the surface and that “rolled-after heat-treatment and hot-dipped” shows a contraire residual stress path as “rolled-before heat-treatment and galvanized” with a maximum below the surface.

Keywords
HT-Bolts, Deep Rolling, Residual Stress Measurement, Neutron Diffraction

Published online 9/11/2018, 6 pages
Copyright © 2018 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: J. Unglaub, J. Hensel, R. Wimpory, T. Nitschke-Pagel, K. Dilger, K. Thiele, ‘Analysis of Residual Stress State in Deep-Rolled HT-Bolts’, Materials Research Proceedings, Vol. 6, pp 209-214, 2018

DOI: http://dx.doi.org/10.21741/9781945291890-33

The article was published as article 33 of the book Residual Stresses 2018

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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