Effect of ageing on transformation kinetics and internal friction of Ni-rich Ni–Ti alloys

Marjaana Peltonen (Corresponding Author), Tomi Lindroos, Marke Kallio

Research output: Contribution to journalArticleScientificpeer-review

15 Citations (Scopus)

Abstract

In Ni-rich Ni–Ti alloys the ageing treatments create finely dispersed Ti3Ni4 precipitates in the B2-based matrix. Formed precipitates are known to influence the phase transformation temperatures and to facilitate the R-phase transformation. In addition to the change in the phase transformation behaviour, the ageing treatments are also reported to affect internal friction and mechanical properties of Ni–Ti alloys. In the present work, by means of systematic DSC and DMA studies the effects of the ageing treatments on the phase transformation as well as on the internal friction and mechanical properties of Ni-rich Ni–Ti alloy were studied. As an extension to earlier studies, the present study concentrates both on the effects of the ageing time and the ageing temperature systematically. By combining the results of the DSC measurements of phase transformation behaviour to the DMA measurements of internal friction and mechanical behaviour of the Ni-rich Ni–Ti alloy, the present study gives yet unpublished information about the comprehensive effects of the ageing treatments on these alloys. These results enable to control the phase transformation temperatures, internal friction and mechanical properties of the Ni-rich Ni–Ti alloy by selecting the suitable ageing treatment. Results showed that the noticed effects of the ageing treatments on mechanical properties could be explained with the changes in the size, distribution, density and coherency of the formed Ti3Ni4 precipitates. The high internal friction values can be explained as the contribution of the internal stress fields and increased amount of mobile interfaces as the result of the formed Ti3Ni4 precipitates. The amount of mobile interfaces seems to be more dominant factor for the increased internal friction value than the effect of the internal stress fields. Therefore, the optimal internal friction values can be obtained with a proper aging treatment which will yield a high density of small Ti3Ni4 precipitates.

Original languageEnglish
Pages (from-to)237 - 245
Number of pages9
JournalJournal of Alloys and Compounds
Volume460
Issue number1-2
DOIs
Publication statusPublished - 2008
MoE publication typeA1 Journal article-refereed

Fingerprint

Internal friction
Aging of materials
Kinetics
Phase transitions
Precipitates
Mechanical properties
Dynamic mechanical analysis
Residual stresses
Temperature

Keywords

  • Shape memory
  • Phase transitions
  • Thermodynamic properties

Cite this

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title = "Effect of ageing on transformation kinetics and internal friction of Ni-rich Ni–Ti alloys",
abstract = "In Ni-rich Ni–Ti alloys the ageing treatments create finely dispersed Ti3Ni4 precipitates in the B2-based matrix. Formed precipitates are known to influence the phase transformation temperatures and to facilitate the R-phase transformation. In addition to the change in the phase transformation behaviour, the ageing treatments are also reported to affect internal friction and mechanical properties of Ni–Ti alloys. In the present work, by means of systematic DSC and DMA studies the effects of the ageing treatments on the phase transformation as well as on the internal friction and mechanical properties of Ni-rich Ni–Ti alloy were studied. As an extension to earlier studies, the present study concentrates both on the effects of the ageing time and the ageing temperature systematically. By combining the results of the DSC measurements of phase transformation behaviour to the DMA measurements of internal friction and mechanical behaviour of the Ni-rich Ni–Ti alloy, the present study gives yet unpublished information about the comprehensive effects of the ageing treatments on these alloys. These results enable to control the phase transformation temperatures, internal friction and mechanical properties of the Ni-rich Ni–Ti alloy by selecting the suitable ageing treatment. Results showed that the noticed effects of the ageing treatments on mechanical properties could be explained with the changes in the size, distribution, density and coherency of the formed Ti3Ni4 precipitates. The high internal friction values can be explained as the contribution of the internal stress fields and increased amount of mobile interfaces as the result of the formed Ti3Ni4 precipitates. The amount of mobile interfaces seems to be more dominant factor for the increased internal friction value than the effect of the internal stress fields. Therefore, the optimal internal friction values can be obtained with a proper aging treatment which will yield a high density of small Ti3Ni4 precipitates.",
keywords = "Shape memory, Phase transitions, Thermodynamic properties",
author = "Marjaana Peltonen and Tomi Lindroos and Marke Kallio",
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pages = "237 -- 245",
journal = "Journal of Alloys and Compounds",
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}

Effect of ageing on transformation kinetics and internal friction of Ni-rich Ni–Ti alloys. / Peltonen, Marjaana (Corresponding Author); Lindroos, Tomi; Kallio, Marke.

In: Journal of Alloys and Compounds, Vol. 460, No. 1-2, 2008, p. 237 - 245.

Research output: Contribution to journalArticleScientificpeer-review

TY - JOUR

T1 - Effect of ageing on transformation kinetics and internal friction of Ni-rich Ni–Ti alloys

AU - Peltonen, Marjaana

AU - Lindroos, Tomi

AU - Kallio, Marke

PY - 2008

Y1 - 2008

N2 - In Ni-rich Ni–Ti alloys the ageing treatments create finely dispersed Ti3Ni4 precipitates in the B2-based matrix. Formed precipitates are known to influence the phase transformation temperatures and to facilitate the R-phase transformation. In addition to the change in the phase transformation behaviour, the ageing treatments are also reported to affect internal friction and mechanical properties of Ni–Ti alloys. In the present work, by means of systematic DSC and DMA studies the effects of the ageing treatments on the phase transformation as well as on the internal friction and mechanical properties of Ni-rich Ni–Ti alloy were studied. As an extension to earlier studies, the present study concentrates both on the effects of the ageing time and the ageing temperature systematically. By combining the results of the DSC measurements of phase transformation behaviour to the DMA measurements of internal friction and mechanical behaviour of the Ni-rich Ni–Ti alloy, the present study gives yet unpublished information about the comprehensive effects of the ageing treatments on these alloys. These results enable to control the phase transformation temperatures, internal friction and mechanical properties of the Ni-rich Ni–Ti alloy by selecting the suitable ageing treatment. Results showed that the noticed effects of the ageing treatments on mechanical properties could be explained with the changes in the size, distribution, density and coherency of the formed Ti3Ni4 precipitates. The high internal friction values can be explained as the contribution of the internal stress fields and increased amount of mobile interfaces as the result of the formed Ti3Ni4 precipitates. The amount of mobile interfaces seems to be more dominant factor for the increased internal friction value than the effect of the internal stress fields. Therefore, the optimal internal friction values can be obtained with a proper aging treatment which will yield a high density of small Ti3Ni4 precipitates.

AB - In Ni-rich Ni–Ti alloys the ageing treatments create finely dispersed Ti3Ni4 precipitates in the B2-based matrix. Formed precipitates are known to influence the phase transformation temperatures and to facilitate the R-phase transformation. In addition to the change in the phase transformation behaviour, the ageing treatments are also reported to affect internal friction and mechanical properties of Ni–Ti alloys. In the present work, by means of systematic DSC and DMA studies the effects of the ageing treatments on the phase transformation as well as on the internal friction and mechanical properties of Ni-rich Ni–Ti alloy were studied. As an extension to earlier studies, the present study concentrates both on the effects of the ageing time and the ageing temperature systematically. By combining the results of the DSC measurements of phase transformation behaviour to the DMA measurements of internal friction and mechanical behaviour of the Ni-rich Ni–Ti alloy, the present study gives yet unpublished information about the comprehensive effects of the ageing treatments on these alloys. These results enable to control the phase transformation temperatures, internal friction and mechanical properties of the Ni-rich Ni–Ti alloy by selecting the suitable ageing treatment. Results showed that the noticed effects of the ageing treatments on mechanical properties could be explained with the changes in the size, distribution, density and coherency of the formed Ti3Ni4 precipitates. The high internal friction values can be explained as the contribution of the internal stress fields and increased amount of mobile interfaces as the result of the formed Ti3Ni4 precipitates. The amount of mobile interfaces seems to be more dominant factor for the increased internal friction value than the effect of the internal stress fields. Therefore, the optimal internal friction values can be obtained with a proper aging treatment which will yield a high density of small Ti3Ni4 precipitates.

KW - Shape memory

KW - Phase transitions

KW - Thermodynamic properties

U2 - 10.1016/j.jallcom.2007.05.102

DO - 10.1016/j.jallcom.2007.05.102

M3 - Article

VL - 460

SP - 237

EP - 245

JO - Journal of Alloys and Compounds

JF - Journal of Alloys and Compounds

SN - 0925-8388

IS - 1-2

ER -