Effects of grain refinement on the microstructures and damping behaviors of a Cu–Al–Ni–Mn–Ti shape memory alloy. (November 2021)

• Record Type: Journal Article
• Authors: Yao, Chang; Yin, Fuxing; Ji, Puguang; Hao, Gangling; Jiao, Zhixian; Liu, Li; Zhang, Jianjun; Cui, Chunxiang; Wang, Qingzhou
• Is Part Of: Intermetallics. Volume 138(2021)
• Publication Date: 2021-11
• Subjects: Cu–Al–Ni–Mn–Ti -- Al–La–B -- Grain refinement -- Martensitic transformation -- Damping; Intermetallic compounds -- Metallography -- Periodicals; Metallic glasses -- Periodicals; Composés intermétalliques -- Métallographie -- Périodiques; 669.94
• DOI: 10.1016/j.intermet.2021.107315
• Languages: English
• ISSNs: 0966-9795

Abstract

Abstract: Grains of a Cu–Al–Ni–Mn–Ti shape memory alloy (SMA) were remarkably refined by the Al–La–B inoculant. Evolution of microstructures and changes of both martensitic transformation (MT) temperatures and damping property of the Cu–Al–Ni–Mn–Ti SMA were also systematically investigated. It was found that with increasing the adding amount of inoculant, the grain size decreased first and then increased, whereas the damping increased first and then decreased. When the adding amount of inoculant reached 2.5 wt%, the smallest grains and the highest damping could be obtained. The improvement of damping could be attributed to the increased density of interfaces between matensite lamellae and between twins. Moreover, with increasing the adding amount of inoculant, all characteristic temperatures of both reverse and forward MT shift to high temperature side. This could be ascribed to the decreased Al content in the Cu–Al–Ni–Mn–Ti SMA due to the formation of Al11 La3 phase. In addition, this is also related to the changes of the density of grain boundaries and the order degree of the Cu–Al–Ni–Mn–Ti SMA. Highlights: Cu–Al–Ni–Mn–Ti SMA were refined by Al–La–B inoculant for the first time. Evolution rule of microstructures after grain refinement were investigated. The damping capacity could be remarkably improved after grain refinement. Interestingly, Ti-rich precipitated particles were covered with Al11 La3 band. The related mechanisms were analyzed in detail.