Effect Of Ageing On Damping Characteristics Of Cu-Al-Be-Mn Quaternary Shape Memory Alloys

• Published in: Materials today : proceedings Vol. 4; no. 10; pp. 11314 - 11317
• Main Authors: Shivaramu, L., Shivasiddaramaiah, A.G., Mallik, U.S., Prashantha, S.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 2017
• Subjects: Ageing; CuAlBeMn; DMA; DSC; SMAs; DMA; SMAs; CuAlBeMn; DSC; Ageing
• ISSN: 2214-7853; 2214-7853
• DOI: 10.1016/j.matpr.2017.09.056

Generally SMAs dissipate energy during hysteretic cycles for larger strain amplitudes. This is due to stress-induced martensitic transformation. The ageing effect on the damping properties of CuAlBeMn quaternary shape memory alloy was studied. The alloy was prepared by using induction melting technique. Prepared alloys were homogenized at 900°C for about 6 hours then hot rolled into 1mm thick sheets followed by betatization at 900°C for about 30 minutes. The specimens were aged at 250°C and 500°C for 1,2, and 3 hours respectively for both the temperatures. In particular four different compositions of CuAlBeMn are characterized using SEM, DSC and DMA for microstructure, transformation temperatures and damping limits of the aged specimens. Damping limits are determined for 1 Hz of frequency and 1micrometer amplitude. The alloys exhibit decrease in damping limit as the ageing temperature and time increases due to the formation of precipitate particles which in turn act as hindrance for the movement of interfaces.