On the transformation behaviour of NiTi particulate reinforced AA2124 composites

Abstract

a b s t r a c tThe transformation behaviour of AA2124 alloys reinforced with NiTi particulates of 10 vol pct and 20 vol pct has been studied by differential scanning calorimetry (DSC), thermoelectric power (TEP) and internal friction (IF). Addition of NiTi particulates increases the damping capacity as well as the precipitation kinetics of AA2124 composites with respect to the base AA2124. Heat treatments performed to change the matrix condition do not alter the transformation significantly, other than homogeneising the Al level in the particulates, which is present due to the preceding extrusion treatment. The presence of Al in NiTi stabilizes the R-phase transformation but the M s remains stable.

Design, Fabrication, and Properties of High Damping Metal Matrix Composites—A Review

“…Because the martensite phase of SMAs has a comparatively high loss factor, an improvement in the damping capacity of the SMA particulate-reinforced composites is expected at the martensite stage. Consistent with the aforementioned work, Thorat et al [39] showed that addition of NiTi particulates increased the damping capacity as well as the precipitation kinetics of AA2124 composites compared with the base AA2124. San Juan and No [40] developed a new kind of high damping metal matrix composites, based on powders of Cu–Al–Ni shape memory alloys (SMAs) embedded in an indium matrix.…”

“…Quantitative comparison of the damping capacity of materials is difficult, because of the differences in testing method (torsion pendulum methods [5,21,24,27,30,39,42,52,53,67], suspended beam method [4,14,16,18,29], dynamic mechanical thermal analyzer technique [12,15,17,19,22,25,31], Piezoelectric ultrasonic composite oscillator technique), exciting mode (impulse excitation [4,16,18], forced vibration [24,27,30,67], free decay [5,23,39], resonant vibration [30]), testing parameters (temperature, the loading frequency, strain amplitude) [70,71], and specimen configuration (wire, rod, sheet). On the other hand, measures of damping capacity include loss angle (φ), loss tangent (tan φ), inverse quality factor (Q -1 ), loss factor (η), logarithmic decrement (δ) and specific damping capacity (SDC, ψ).…”

On the production and properties of novel particulate NiTip/AA2124 metal matrix composites

“…NiTi particulates are homogeneously distributed in the aluminium matrix. In contrast to a previous attempt to make such composites [7], no intermetallic phases were detected at the interface between NiTi/Al matrix; however, SEM-EDS chemical analyses show that some Al and Cu have diffused into the NiTi particulates. These elements are homogeneously distributed inside the NiTi particulates, whose composition is very similar in composites 10R and 20R: 51Ni-41Ti-6Al-2Cu (in wt.%).…”

Deformation Mechanisms in NiTi-Al Composites Fabricated by Ultrasonic Additive Manufacturing

“…Metal matrix composites (MMCs) with shape memory alloy (SMA) reinforcements have attracted increased attention [1,2] due to an increased demand for lightweight smart materials in the automotive, biomedical, and aerospace industries [3,4]. Aluminum matrix composites containing aligned NiTi SMA wires are candidates for light-weight, low thermal expansion applications.…”

“…In constrast, other SMAreinforced MMCs in the literature [1,18,19] involve embedding techniques at or above the recrystallization temperatures of the components. These embedding techniques are therefore above the A f temperature of SMAs and therefore do not permit the control of oriented martensite that is possible in the present work.…”