Structural Internal Friction in CuAlNi Crystals

Aging response and its effect on the functional properties of Cu–Al–Ni shape memory alloys

“…In the as-grown condition and at room temperature, alloy M is in the martensite state whereas alloy A is in the austenite state. Prior to the experiments, samples were homogenized for 60 min at 1223 K and for 15 min at 1173 K for alloys A and M, respectively [3,5,10,13]. The alloy A was quenched in a mixture of ice and water, and the alloy M was quenched into water.…”

“…Specifically, Cu-Al-Ni single crystal alloys can exhibit shape memory properties to a temperature of ∼200 • C [1] and a large recoverable non-linear superelastic strain of ∼18% [2]. Moreover, the Cu-Al-Ni alloys exhibit good damping or internal friction (IF) due to their unique martensitic transition characteristics [3]. Their high IF, especially during transformation and in the martensitic state, is closely related to the mobility of the parent/martensite and martensite/martensite interfaces [3,4].…”

“…Moreover, the Cu-Al-Ni alloys exhibit good damping or internal friction (IF) due to their unique martensitic transition characteristics [3]. Their high IF, especially during transformation and in the martensitic state, is closely related to the mobility of the parent/martensite and martensite/martensite interfaces [3,4]. * Corresponding author.…”

“…A good understanding of the damping property variation with aging treatments can also be utilized to design tailor-made materials for specific applications. However, only a limited number of studies were performed on the damping properties of aged martensitic alloy [3,5] and no reports are available in open literature on the aged austenitic alloy. The objective of the present work is two-fold, first is to conduct a systematic study on the aging behaviour at three different temperatures in the parent phase that correspond to the three stages of aging [8].…”

Low Frequency Amplitude - Dependent Relaxation in Cu-Al-Ni Crystals

“…Detailed investigations have revealed that fr-equency dependence of the intrinsic A D F in martensitic phase of Cu-Al-Ni crystals does exist [5]. At room temperature, the most pronounced frequency dependence in quenched crystals was claimed to be determined mainly by an interaction of mobile partial dislocations in PI' martensite with mobile short range point obstacles (PO) [5,6].…”