Martensitic Transformation in Thin Foil Specimen of a Shape Memory TiNi Alloy

Microstructures and transformation behavior of TiNi shape memory alloy after high temperature ECAE process have been investigated. It is found that the initial coarse grains were refined after high temperature ECAE processes and short annealing at 750°C. Transformation temperatures of TiNi alloy sharply decreased after two ECAE processes, rose obviously when annealed at 750°C for 5min, and quickly rose back after annealing at 500°C for 2 hours. Reasons for phase transformation behavior changes have been discussed.

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Investigation on Ce Addition on Microstructure and Martensitic Transformation of a Ti51Ni49 Shape Memory Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.852.28 ◽

2016 ◽

Vol 852 ◽

pp. 28-32

Author(s):

Ai Lian Liu ◽

Nan Nan Mao ◽

Jia Wen Xu ◽

Wei Cai

Keyword(s):

Martensitic Transformation ◽

Shape Memory Alloy ◽

Shape Memory ◽

Ternary Alloys ◽

Tini Alloy ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

The Matrix ◽

One Step ◽

Electronic Microscope

The effect of rare earth element Ce addition on the microstructure and martensitic transformation behavior of Ti51Ni49 shape memory alloy was investigated by scanning electronic microscope (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The results show that the microstructure of TiNiCe ternary alloy consists of Ti2Ni phase, CeNi phase and the matrix. One-step martensitic transformation is observed in quenched TiNiCe ternary alloys, which is the same as that in quenched TiNi binary alloys. The martensitic transformation temperatures of Ti-rich TiNi alloy hardly increase with Ce addition.

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Unusual Multistage Martensitic Transformation in TiNi Shape Memory Alloy after Thermal Cycling

Materials Science Forum ◽

10.4028/www.scientific.net/msf.738-739.372 ◽

2013 ◽

Vol 738-739 ◽

pp. 372-376 ◽

Cited By ~ 10

Author(s):

Aleksey Sibirev ◽

Sergey Belyaev ◽

Natalia Resnina

Keyword(s):

Martensitic Transformation ◽

Shape Memory Alloy ◽

Thermal Cycling ◽

Shape Memory ◽

Temperature Interval ◽

Defect Structure ◽

Tini Alloy ◽

Thermal Cycles ◽

Unusual Phenomenon ◽

Kinetics Of

Variation in kinetics of martensitic transformation, in an equiatomic TiNi shape memory alloy, during thermal cycles was investigated. Samples annealed at 500 °C for 1 hour were subjected to repeated thermal cycles, through the temperature range of martensitic transformation. Unusual 4-stage martensitic transformation during cooling after 30 thermal cycles was observed. Moreover, a new unusual phenomenon was found in the preliminary thermal cycled TiNi alloy. It was observed that variation in the highest temperature Th of thermal cycles temperature interval resulted in the redistribution of released heat among four calorimetric peaks, observed on cooling. It was found that if the Th temperature did not exceed 240 °C the variation in kinetics was repeatable, and determined only by the value of Th. It was assumed that the defect structure induced on preliminary thermal cycling changes reversibly on cooling and heating.

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Influence of irreversible plastic deformation on the martensitic transformation and shape memory effect in TiNi alloy

Materials Science and Engineering A ◽

10.1016/j.msea.2006.02.067 ◽

2006 ◽

Vol 438-440 ◽

pp. 627-629 ◽

Cited By ~ 8

Author(s):

S.P. Belyaev ◽

N.N. Resnina ◽

A.E. Volkov

Keyword(s):

Plastic Deformation ◽

Martensitic Transformation ◽

Shape Memory ◽

Shape Memory Effect ◽

Memory Effect ◽

Tini Alloy

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Microstructure Evolution and Mechanical Behavior in Shape Memory Nanostructured TiNi Alloy

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.385.169 ◽

2018 ◽

Vol 385 ◽

pp. 169-174 ◽

Cited By ~ 2

Author(s):

Anna Misochenko ◽

Jeevanandham Vijaya Tilak Kumar ◽

Sudha Jayaprakasam ◽

K. Anantha Padmanabhan ◽

Vladimir Stolyarov

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Martensitic Transformation ◽

Shape Memory Alloy ◽

Shape Memory ◽

Microstructure Evolution ◽

Mechanical Response ◽

Coarse Grained ◽

Tini Alloy ◽

Nanostructured Alloys

Influence of grain size on the martensitic transformation and mechanical properties of shape memory alloy Тi49.3Ni50.7 was studied. The features of the mechanical response of coarse-grained and nanostructured alloys were identified. The microstructure investigations involved the use of TEM and SEM.

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