TY - JOUR

T1 - The effect of isothermal holding on reversible and irreversible strain in TiNi shape memory alloy

AU - Resnina, N.

AU - Sibirev, A.

AU - Belyaev, S.

AU - Gracheva, A.

PY - 2017

Y1 - 2017

N2 - An influence of relaxation processes occurred on holding of the Ti50Ni50 alloy at a high temperature on the accumulation of the reversible and irreversible strain on cooling and heating of the sample under a constant stress of 50MPa through a temperature range of the martensitic transformation was studied. It was found that a holding of the sample at temperatures which were higher than Af temperature (finish temperature of the reverse transformation) led to an increase in reversible strain and influenced in a different way on an irreversible strain accumulated in the sample after holding. If a holding temperature was less than 160 oC, then an increase in holding duration resulted in a decrease in irreversible strain accumulated in the sample on cooling under a stress of 50 MPa. If the holding temperature was equal to 160 oC than the holding of the sample did not influence the irreversible strain. In the case of the holding temperature was larger than 160 oC, the irreversible strain increased on a rise in a holding duration. It was assumed that a difference in dependences of the irreversible stain on the holding duration observed at different holding temperature was due to relaxation was a thermally activated process and its intensity depended on a holding temperature.

AB - An influence of relaxation processes occurred on holding of the Ti50Ni50 alloy at a high temperature on the accumulation of the reversible and irreversible strain on cooling and heating of the sample under a constant stress of 50MPa through a temperature range of the martensitic transformation was studied. It was found that a holding of the sample at temperatures which were higher than Af temperature (finish temperature of the reverse transformation) led to an increase in reversible strain and influenced in a different way on an irreversible strain accumulated in the sample after holding. If a holding temperature was less than 160 oC, then an increase in holding duration resulted in a decrease in irreversible strain accumulated in the sample on cooling under a stress of 50 MPa. If the holding temperature was equal to 160 oC than the holding of the sample did not influence the irreversible strain. In the case of the holding temperature was larger than 160 oC, the irreversible strain increased on a rise in a holding duration. It was assumed that a difference in dependences of the irreversible stain on the holding duration observed at different holding temperature was due to relaxation was a thermally activated process and its intensity depended on a holding temperature.

U2 - 10.1016/j.matpr.2017.04.064

DO - 10.1016/j.matpr.2017.04.064

M3 - Article

VL - 4

SP - 4748

EP - 4752

JO - Materials Today: Proceedings

JF - Materials Today: Proceedings

SN - 2214-7853

IS - 3PB

ER -