PSI - Issue 69

Available online at www.sciencedirect.com

ScienceDirect

Procedia Structural Integrity 69 (2025) 61–68

13th European Symposium on Martensitic Transformation 2024 (ESOMAT 2024) Improvement of Mechanical Behaviour in B doped Ni3Ta based High Temperature Shape Memory Alloy Carlo Alberto Biffi*, Jacopo Fiocchi, Jannis Nicolas Lemke, Alberto Coda, Ausonio Tuissi National Research Council of Italy – Institute of Condensed Matter Chemistry and Technologies for Energy, Via Previati 1E, Lecco, 23900, Italy. Abstract Shape memory alloys (SMAs) able to exhibit the martensitic transformation (MT) at high temperature (above 100°C) are very attractive smart materials for some industrial sectors, such as automotive and aerospace ones. Their main issues regard the brittleness, limiting their processing, and the unstable functionality upon thermal cycling. In this work, the effect of B addition (0.8% in atomic percentage) in the place of Ni and Ta in Ni3Ta SMA on the MT, microstructure and mechanical properties is studied. It is found that the MT occurs above 200°C and its thermal stability can be reached after few thermal cycles. The addition of B in limited amount does not suppress the MT and it improves the mechanical properties in compression, reducing the cracking behavior in comparison to the binary alloy. © 2025 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 Guest Editors

Keywords: Type your keywords here, separated by semicolons ;

1. Introduction In the last years great efforts have been focused on the development of shape memory alloys (SMAs) for high temperature (HT) applications, that perform above at least 100°C, for different potential industrial fields, such as automotive, aerospace, mechanical and control systems [1,2]. A relevant number of works can be found in the

* Corresponding author. Tel.: +39-0341-2350111. E-mail address: carloalberto.biffi@cnr.it

2452-3216 © 2025 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 Guest Editors 10.1016/j.prostr.2025.07.009