PSI - Issue 59

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2023) 000 – 000

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 59 (2024) 265–270

© 2024 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of DMDP 2023 Organizers Abstract The report contains the results of experimental studies of the influence of warm prestressing (WPS) in load modes I and II on fracture toughness of steels in modes II and I, respectively. The studies were performed on reactor pressure vessel steels 15Kh2MFА(II) , 15Kh2NМFА (II) and 10GN2MFA with different mechanical properties. It was found that WPS under mode II causes an increase in the mode II fracture toughness and decrease under mode I for brittle reactor steels and exhibits a slight influence on the plastic reactor steels, which is due to asymmetric distribution of residual stresses along the crack faces. The results of studies of static crack resistance, as well as the effect of WPS at different ratios of mixed modes of deformation (I+II+III), performed on a prismatic sample AFM (all fracture mode specimen) of the type of the Richard specimen, are shown. It was established that the fracture toughness (I+II+III) due to WPS is increased with the corresponding ratio (I+II+III) of the deformation modes. However, it is noted that as the preliminary load increases in the longitudinal and transverse shear components, the effect of WPS on fracture toughness decreases. The established regularities should be taken into account when calculating the residual life of elements of power equipment. © 2024 The Authors. Publish ed by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of DMDP 2023 Organizers Keywords: mixed mode; fracture tougness; warm prestressing; reactor steels VII International Conference “In -service Damage of Materials: Diagnostics and Prediction ” (DMDP 2023) Prediction of the effect of warm prestressing on the mixed mode fracture toughness of the reactor pressure vessel steels V. Sidyachenko*, V. Pokrovskii G. S. Pisarenko Institute for Problems of Strength of the NAS of Ukraine, 2 Sadovo-Botanichna str., Kyiv-014, 01014, Ukraine

* Corresponding author. Tel.: +380 44 281 63 39 ; fax: +380 44 286 16 84. E-mail address: Sydiachenko@ukr.net

2452-3216 © 2024 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of DMDP 2023 Organizers

2452-3216 © 2024 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of DMDP 2023 Organizers 10.1016/j.prostr.2024.04.038