Enhancement of superelastic property in Ti–Zr–Ni–Cu alloy by using glass alloy precursor with high glass forming ability

Ti-based alloy Ti75Zr11Si9Fe5 (At %) and Ti66Zr11Si15Fe5Mo3 (At %) ribbons are fabricated by a single roller spun-melt technique, according to the three empirical rules. Both alloys are found to have a large, supercooled liquid region (ΔTx) before crystallization that reaches 80–90 K. The results show that both alloys possess excellent glass-forming abilities. The electrochemical measurement proves both amorphous alloys possess relatively high corrosion resistance in 3 mass% NaCl solution.

Section: Resultsmentioning

confidence: 99%

Glass-Forming Ability and Corrosion Behavior of Ti-Based Amorphous Alloy Ti-Zr-Si-Fe

Bai¹,

Ding²,

Zhang³

et al. 2022

“…In the AAPs for SMA, the alloy composition is also important to determine the crystallization kinetics. Kim et al [118] systematically demonstrated the effect of alloying elements on the crystallization kinetics in the melt-spun Ni-Ti-Zr-Cu AAPs through substitution of Zr for Ti. With regard to the crystallization kinetics of melt-spun Ni 35 Ti 50-x Zr x Cu 15 AAPs with x = 5, 10, 15, 20 at.%, Zr acts as an element that hinders crystal growth due to its large atomic radius and low diffusivity.…”

Section: Formation and Characterization Of Ultrafine Niti-based Smas ...mentioning

confidence: 99%

“…Moreover, the increase in Zr content induced the formation of a wavy grain boundary. These microstructural evolutions, such as grain refinement and wavy grain boundaries, could suppress the martensitic transformation by changing the thermodynamic balance condition [118,119]. For the strain recovery behavior of SMAs, the grain refinement of SMAs brings a positive effect due to the enhanced resistance to slip deformation.…”

Section: Formation and Characterization Of Ultrafine Niti-based Smas ...mentioning

confidence: 99%

Recent Developments in Ultrafine Shape Memory Alloys Using Amorphous Precursors

Hong,

Park,

Song

et al. 2023

Self Cite

In this review, we systematically reviewed the recent advances in the development of ultrafine shape memory alloys with unique shape memory effects and superelastic behavior using amorphous metallic materials. Its scientific contribution involves defining and expanding the range of fabrication methods for single-phase ultrafine/nanocrystalline alloys with multicomponent systems. In multicomponent amorphous alloys, the crystallization mechanism depends on the alloy composition and is a selectable factor in the alloy designing method, considering the thermodynamic and physical parameters of constituent elements. The crystallization kinetics can be controlled by modulating the annealing condition in a supercooled liquid state with consideration of the crystalline temperature of the amorphous alloys. The phase stability of austenite and martensite phases in ultrafine shape memory alloys developed from amorphous precursors is determined according to alloy composition and grain size, which strongly influence the shape memory effect and superelastic behavior. A methodological framework is subsequently suggested to develop the ultrafine shape memory alloys based on the systematic alloy designing method, which can be considered an important strategy for developing novel ultrafine/nanocrystalline shape memory alloys with excellent shape memory and superelastic effects.

“…SMA with martensitic phase has good shape memory effect, that is, the alloy with a specific composition can be loaded and deformed in martensitic phase state, and retain its deformed shape after unloading, and then the deformed alloy can be restored to the shape before loading when heated to the parent phase state [8]. SMA with the parent phase state has good superelasticity, that is, the strain produced by a specific component alloy under the action of external force exceeds its elastic limit variable, after unloading, the alloy can spontaneously restore to its original shape [9,10,11], and its stress-strain curve presents as non-linear. In addition, the Ti–Ni-based SMA has high damping properties, biocompatibility, and corrosion resistance, and has been applied in aerospace, machinery manufacturing, transportation, civil construction, energy engineering, biomedicine, and daily life [12,13,14,15].…”

Section: Introductionmentioning

confidence: 99%

Effect of Heat Treatment Temperature on Martensitic Transformation and Superelasticity of the Ti49Ni51 Shape Memory Alloy

Yong-shan

Meng

et al. 2019

The martensitic transformation and superelasticity of Ti49Ni51 shape memory alloy heat-treatment at different temperatures were investigated. The experimental results show that the microstructures of as-cast and heat-treated (723 K) Ni-rich Ti49Ni51 samples prepared by rapidly-solidified technology are composed of B2 TiNi phase, and Ti3Ni4 and Ti2Ni phases; the microstructures of heat-treated Ti49Ni51 samples at 773 and 823 K are composed of B2 TiNi phase, and of B2 TiNi and Ti2Ni phases, respectively. The martensitic transformation of as-cast Ti49Ni51 alloy is three-stage, A→R→M1 and R→M2 transformation during cooling, and two-stage, M→R→A transformation during heating. The transformations of the heat-treated Ti49Ni51 samples at 723 and 823 K are the A↔R↔M/A↔M transformation during cooling/heating, respectively. For the heat-treated alloy at 773 K, the transformations are the A→R/M→R→A during cooling/heating, respectively. For the heat-treated alloy at 773 K, only a small thermal hysteresis is suitable for sensor devices. The stable σmax values of 723 and 773 K heat-treated samples with a large Wd value exhibit high safety in application. The 773 and 823 K heat-treated samples have large stable strain–energy densities, and are a good superelastic alloy. The experimental data obtained provide a valuable reference for the industrial application of rapidly-solidified casting and heat-treated Ti49Ni51 alloy.