Influence of the holding temperature on the kinetics of the isothermal B2 → B19′ transformation in TiNi-based shape memory alloy

Demidova, Elena; Belyaev, Sergey; Resnina, Natalia; Shelyakov, A. V.

doi:10.1007/s10973-019-08717-4

Cited by 14 publications

(7 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

Section: Introductionmentioning

confidence: 96%

“…The realization of the forward B2 → B19' thermoelastic martensitic transformation under isothermal conditions was found in NiTi-based alloys with non-stoichiometric composition [1][2][3][4][5]. The volume fraction of the isothermal martensitic depended on the position of the holding temperature compared to the M s temperature and on the chemical composition of the alloy [4][5]. For example, during holding at the M s temperature, 45 % of martensite appeared isothermally in the quenched Ni 51 Ti 49 alloy and 80 % -in the Ti 40.7 Hf 9.5 Ni 44.8 Cu 5 alloy [4][5].…”

Section: Introductionmentioning

confidence: 97%

“…The volume fraction of the isothermal martensitic depended on the position of the holding temperature compared to the M s temperature and on the chemical composition of the alloy [4][5]. For example, during holding at the M s temperature, 45 % of martensite appeared isothermally in the quenched Ni 51 Ti 49 alloy and 80 % -in the Ti 40.7 Hf 9.5 Ni 44.8 Cu 5 alloy [4][5]. In a quenched Ni-rich NiTi alloy, excess Ni atoms replace Ti atoms in the Ti sub-lattice and become the substitutional defects.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The strain variation during the isothermal B2→B19’ martensitic transformation in the quenched or annealed Ni₅₁Ti₄₉ alloy

Ivanov

Gabrielian

Belyaev

et al. 2022

IOP Conf. Ser.: Mater. Sci. Eng.

View full text Add to dashboard Cite

The strain variation during the isothermal holding under constant stress was studied in the quenched or annealed Ni51Ti49 alloy samples. The isothermal strain variation was found in both samples and this strain was completely recovered on subsequent unloading and heating. This allowed to conclude that the strain variation on holding was caused by the isothermal martensitic transformation. It was found that the maximum value of isothermal strain depended on the alloy heat treatment. This value was equal to 0.5 % in annealed sample and it was equal to 6 % in quenched sample. It was assumed that the formation of the Ni4Ti3 phase during annealing led to a decrease in concentration of substitutional Ni atoms in NiTi phase that were responsible for the isothermal transformation. As a result, the less volume fraction of the martensite formed during holding that supresses the strain variation in annealed samples.

show abstract

Section: Introductionmentioning

confidence: 96%

Section: Introductionmentioning

confidence: 97%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The strain variation during the isothermal B2→B19’ martensitic transformation in the quenched or annealed Ni₅₁Ti₄₉ alloy

Ivanov

Gabrielian

Belyaev

et al. 2022

IOP Conf. Ser.: Mater. Sci. Eng.

View full text Add to dashboard Cite

show abstract

“…Recently, it has been shown that some NiTi-based shape memory alloys undergo the forward martensitic transformation during holding at a constant temperature close to M s (start temperature of the forward martensitic transition) [1][2][3][4][5][6][7]. The kinetics of this process is well studied experimentally, and it is established that the martensite volume fraction increases with time up to a saturation value, which depends on the holding temperature in a nonmonotonic way [5 -7].…”

Section: Introductionmentioning

confidence: 99%

Simulation of isothermal reversible strain in the Ti40.7Hf9.5Ni44.8Cu5 alloy using a microstructural model

Demidova

Belyaev

et al. 2021

Lett. Mater.

Self Cite

View full text Add to dashboard Cite

Recently it has been found that some NiTi-based alloys may undergo the forward martensite transition on isothermal holding. Moreover, such isothermal transformation under stress is accompanied by variation in reversible strain. At the same time, theoretical models do not allow describing the recoverable strain variation during holding. The aim of the present study was to adjust the microstructural model earlier developed by V. Likhachev and A. Volkov for describing strain variation due to the formation of the martensite phase on holding of NiTi-based alloys under a constant stress at temperatures within the temperature range of the forward martensite transformation. To take into account the possibility for isothermal martensite formation, a new suggestion was made, according to which the isothermal kinetics might be controlled by some relaxation process, which could change the local density of point defects and led to the fulfillment of thermodynamics condition for transformation. To include this assumption into the model some modifications have been added to constitutive equations. The modified microstructural model was used to simulate the strain variation, caused by isothermal martensite formation under various stresses. The influence of holding parameters (temperature and stress) on the maximum isothermal strain was found, and a good agreement between the simulated and experimental results was obtained. It was shown that the modified microstructural model allowed predicting the holding temperature and the stress at which the maximum isothermal strain can be found.

show abstract

“…In recent years, it has been found that in some NiTi-based alloys, the thermoelastic martensitic transformation can occur during holding at a constant temperature that is higher than the starting temperature of the forward transition M s [1][2][3][4][5][6][7] or within the temperature range of the forward transformation [1, 5 -10]. This phenomenon has been well studied experimentally and the kinetics of this process is described in [4 -6].…”

mentioning

confidence: 99%

Simulation of isothermal kinetics of martensitic transformation in the Ti40.7Hf9.5Ni44.8Cu5 alloy

2020

Self Cite

View full text Add to dashboard Cite

The realization of forward martensitic transformation under isothermal conditions in NiTi-based alloys has been well studied experimentally, along with the kinetics of this process. However, existing models do not allow the isothermal martensite volume fraction Φ M to be estimated, hence the influence of holding temperature or time on the Φ M value could not be calculated. The Johnson-Mehl-Avrami-Kolmogorov (JMAK) theory is normally used to describe isothermal kinetics, but it has not been applied for martensite transformation, which occurs in shape-memory alloys during holding at a constant temperature. Thus, the aim of the present study is to adapt the JMAK theory and use to estimate Φ M variation with time during holding of Ti 40.7 Hf 9.5 Ni 44.8 Cu 5 alloy at different temperatures. The JMAK equation allows the variation of the isothermal martensite volume fraction with time during holding at constant temperatures to be approximated. It was applied to estimate experimental Φ M (t) curves in Ti 40.7 Hf 9.5 Ni 44.8 Cu 5 alloy and a good approximation was established. The dependencies of JMAK-like equation parameters on the holding temperature were also found and approximated. Thus, the expression for the dependence of the isothermal martensite volume fraction on holding temperature and time was found and calculation of the Φ M (t) curves was carried out. The simulated and experimental data for the Ti 40.7 Hf 9.5 Ni 44.8 Cu 5 shape memory alloy were shown to be in good agreement.

show abstract

Influence of the holding temperature on the kinetics of the isothermal B2 → B19′ transformation in TiNi-based shape memory alloy

Cited by 14 publications

References 20 publications

The strain variation during the isothermal B2→B19’ martensitic transformation in the quenched or annealed Ni₅₁Ti₄₉ alloy

The strain variation during the isothermal B2→B19’ martensitic transformation in the quenched or annealed Ni₅₁Ti₄₉ alloy

Simulation of isothermal reversible strain in the Ti40.7Hf9.5Ni44.8Cu5 alloy using a microstructural model

Simulation of isothermal kinetics of martensitic transformation in the Ti40.7Hf9.5Ni44.8Cu5 alloy

Contact Info

Product

Resources

About

Influence of the holding temperature on the kinetics of the isothermal B2 → B19′ transformation in TiNi-based shape memory alloy

Cited by 14 publications

References 20 publications

The strain variation during the isothermal B2→B19’ martensitic transformation in the quenched or annealed Ni51Ti49 alloy

The strain variation during the isothermal B2→B19’ martensitic transformation in the quenched or annealed Ni51Ti49 alloy

Simulation of isothermal reversible strain in the Ti40.7Hf9.5Ni44.8Cu5 alloy using a microstructural model

Simulation of isothermal kinetics of martensitic transformation in the Ti40.7Hf9.5Ni44.8Cu5 alloy

Contact Info

Product

Resources

About

The strain variation during the isothermal B2→B19’ martensitic transformation in the quenched or annealed Ni₅₁Ti₄₉ alloy

The strain variation during the isothermal B2→B19’ martensitic transformation in the quenched or annealed Ni₅₁Ti₄₉ alloy