Full-field stress and strain measurements revealing energy dissipation characteristics in martensitic band of Cu-Al-Mn shape memory alloy. (September 2020)

• Record Type: Journal Article
• Authors: Su, Tung-Huan; Lu, Nian-Hu; Chen, Chih-Hsuan; Chen, Chuin-Shan
• Is Part Of: Materials today communications. Volume 24(2020)
• Publication Date: 2020-09
• Subjects: Full-field stress and strain measurements -- Data-driven stress identification -- Digital image correlation -- Energy dissipation -- Shape memory alloy; Materials science -- Periodicals; 620.11
• DOI: 10.1016/j.mtcomm.2020.101321
• Languages: English
• ISSNs: 2352-4928

Abstract

Graphical abstract: Highlights: Full-field stress fields can be obtained from digital images correlation technique using data-driven identification method without constitutive relationship. It's the first time that this coupled technique is applied to reveal important physics behind mechanical behavior of materials. Martensitic transformation and energy dissipation characteristics of shape memory alloys were studied with the measured stress and strain fields. The energy dissipation feature localizes at regions that undergo martensitic transformation. The local dissipation energy in martensitic bands can be twice the average value of the bulk materials. Abstract: Cu-based shape memory alloys have shown great potential for seismic applications, due to their excellent superelasticity and damping capacity. Understanding energy dissipation from the phase transformation is key to improving the performance of these alloys. In this work, we apply the data-driven identification method (DDI) combined with digital image correlation measurements to study the local energy dissipation characteristics of a Cu-Al-Mn single-crystal alloy. We find that the superelasticity behavior, e.g., the overall mechanical response of the shape memory alloys, can be captured by the DDI method. The measured stress and strain fields help to reveal martensite phase transformation zones and energy dissipation features. We find that the dissipated energy occurs mainly in the interfacial region of the martensite to austenite transformation. Energy is dissipated at the pathway of the moving interfaces during the associated forward/reverse martensitic transformation. The local specific dissipation energy in martensitic bands can be twice the average value of the bulk materials.