An experimental study was performed to determine the effect of aging on martensitic transformations in NiTi, Polycrystalline and single crystal NiTi ([100], [110], and [111] orientations) were both considered, Stress-induced transformations in polycrystalline NiTi were found to closely resemble transformations in single crystals of the [110] and [111] orientations. Solutionized and over-aged single crystals exhibited a strong orientation dependence of the critical stress required to trigger the transformation, σcr The Schmid law was able to accurately predict the orientation dependence of σcr in the solutionized and over-aged single crystals. Peak-aged single crystals demonstrated a much weaker orientation dependence of σcr and in general, the Schmid law was not obeyed. By considering the local stress fields outside of the semi-coherent precipitates, the decrease in the orientation dependence of σcr was accounted for. The martensite start temperatures, Ms, in aged single crystal and polycrystalline NiTi were much higher than in solutionized samples In peak-aged NiTi the increase was primarily attribited to the local stress fields outside the coherent precipitates which create preferential nucleation sites for the martensite. In the over-aged NiTi the increase in Ms was primarily attributed to the decrease in the average Ni concentration of the matrix surrounding the coarsened precipitates.

1.
Abujudom
D. N.
,
Thoma
P. E.
, and
Fariabi
S.
,
1990
, “
The Effect of Cold Work and Heat Treatment on the Phase Transformations of Near Equiatomic NiTi Shape Memory Alloy
,”
Mat. Sci. Forum
, Vol.
56-58
, pp.
565
570
.
2.
Boyd
J. G.
, and
Lagoudas
D. C.
,
1996
, “
A Thermodynamical Constitutive model for Shape Memory Materials. Part 1. The Monolithic Shape Memory Alloy
,”
Int. J. Plasticity
, Vol.
12
, p.
805
805
.
3.
Boyd
J. G.
, and
Lagoudas
D. C.
,
1996
, “
A Thermodynamical Constitutive Model for Shape Memory Materials. Part 2. The SMA Composite Material
,”
Int. J. Plasticity
, Vol.
12
, p.
843
843
.
4.
Buchheit
T. E.
, and
Wert
J. A.
,
1994
, “
Modeling the Effects of Stress State and Crystal Orientation on the Stress-Induced Transformation of NiTi Single Crystals
,”
Metall. Mater. Trans.
, Vol.
25A
, pp.
2383
2389
.
5.
Buchheit
T. E.
, and
Wert
J. A.
,
1996
, “
Predicting the Orientation-Dependent Stress-Induced Transformation and Detwinning Response of Shape Memory Alloy Single Crystals
,”
Metall. Mater. Trans
, Vol.
27A
, pp.
269
279
.
6.
Buehler
W. J.
,
Gilfrich
J. V.
, and
Wiley
R. C.
,
1963
, “
Effect of Low-Temperature Phase Changes on the Mechanical Properties of Alloys near Composition TiNi
,”
J. App. Phys.
, Vol.
34
, pp.
1475
1477
.
7.
Chumlyakov
Y. I.
, and
Starenchenko
S. V.
,
1995
, “
Stress-induced Martensitic Transformation in Aged Titanium Nickel Single Crystals
,”
J. Phys. IV, Colloq
, Vol.
5
, pp.
803
807
.
8.
Chumlyakov
Y. I.
,
Kireeva
I. V.
,
Lineytsev
V. N.
, and
Chepel
E. V.
,
1996
, “
Aging influence on the Shape Memory Effects and Superelasticity in Titanium-Nickel Single Crystals
,”
MRS Symposium Proceedings
, Vol.
459
, Boston, pp.
387
392
.
9.
Duering, T. W., and Pelton, A. R., 1994, “Ti-Ni Shape Memory Alloys,” Mater. Prop. Hnbk., ASM International, Titanium Alloys, pp. 1035–1048.
10.
Falk
F.
,
1989
, “
Pseudoelastic Stress-Strain Curves of Polycrystalline Shape Memory Alloys Calculated from Single Crystal Data
,”
Acta. Met.
, Vol.
27
, pp.
277
277
.
11.
Filip
P.
,
Rusek
J.
, and
Mazanec
K.
,
1991
, “
The Effect of Heat Treatment on the Structural Stability of TiNi Alloys
,”
Z. Met.kd.
, Vol.
82
, pp.
488
491
.
12.
Filip
P.
,
Tomasek
V.
, and
Mazanec
K.
,
1994
, “
Corrosion Properties of Shape Memory TiNi Alloys
,”
Met. Mater.
, Vol.
32
, pp.
63
68
.
13.
Funakubo, H., 1988, Shape Memory Alloys, Gordon and Breach Science.
14.
Furuya
Y.
,
Shimada
H.
,
Tanahashi
Y.
,
Matsumoto
M.
, and
Honma
T.
,
1988
, “
Evaluation of Recovery Bending Force of Shape Memory Ni-Ti Alloy
,”
Scr. Met.
, Vol.
22
, pp.
751
755
.
15.
Gall
K.
,
Sehitoglu
H.
,
Maier
H. J.
, and
Jacobus
K.
,
1988
-A
, “
Stress-Induced Martensitic Phase Transformations in Polycrystalline Cu-Zn-Al Shape Memory Alloys Under Different Stress States
,”
Metall. Mater. Trans.
, Vol.
29
, pp.
765
773
.
16.
Gall, K., and Sehitoglu, H., 1998, “The Role of Texture in Tension-Compression Asymmetry in Polcrystalline NiTi,” in press, Int. J. Plasticity.
17.
Gall, K., Sehitoglu, R., Chumlyakov, Y. I., Kireeva, I., and Maier, H. J., 1998-b, “The Influence of Aging on Critical Transformation Stress Levels and Martensitic Start Temperatures in NiTi: Part I—Microstructure and Micro-Mechanical Modeling,” ASME JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY, Published in this issue, pp. 19–27.
18.
Hodgson
D. E.
,
Wu
M. H.
, and
Biermann
R. J.
,
1990
, “
Shape Memory Alloys
,”
ASM Handbook
, Vol.
2
, pp.
897
902
.
19.
Honma, T., 1986, “The Effect of Aging on the Spontaneous Shape Change and the All-Round Shape Memory Effect in Ni-Rich TiNi Alloy,” ICOMAT-86, pp. 709–716.
20.
Jacobus
K.
,
Sehitoglu
H.
, and
Balzer
M.
,
1996
, “
Effect of Stress State on the Stress-Induced Martensitic Transformation in Polycrystalline Ni-Ti Alloy
,”
Metall. Mater. Trans.
, Vol.
27A
, pp.
3066
3066
.
21.
Li
D. Y.
,
1996
, “
Wear Behavior of TiNi Shape Memory Alloys
,”
Scr. Met.
, Vol.
34
, pp.
195
200
.
22.
Lim
T. J.
, and
McDowell
D. L.
,
1995
, “
Path Dependence of Shape Memory Alloys During Cyclic Loading
,”
J. Int. Mat. Sys. Struct.
, Vol.
6
, pp.
817
830
.
23.
Liu
Y.
, and
Galvin
S. P.
,
1997
, “
Criteria for Pseudoelasticity in Near-Equiatomic NiTi Shape Memory Alloys
,”
Acta Mat.
, Vol.
45
, pp.
4431
4439
.
24.
Miyazaki
S.
,
Ohmi
Y.
,
Otsuka
K.
, and
Suzuki
Y.
,
1982
, “
Characteristics of Deformation and Transformation Pseudoelasticity in Ti-Ni Alloys
,”
J. De. Phys.
, C-4, Vol.
43
, pp.
255
255
.
25.
Miyazaki
S.
,
Kimura
S.
,
Otsuka
K.
, and
Suzuki
Y.
,
1984
, “
The Habit Plane and Transformation Strains Associated With the Martensitic Transformation in Ti-Ni Single Crystals
,”
Scr. Met.
, Vol.
18
, pp.
883
888
.
26.
Miyazaki
S.
,
Imai
T.
,
Igo
Y.
, and
Otsuka
K.
,
1986
, “
Effect of Cyclic Deformation on the Pseudoelastic Characteristics of Ti-Ni Alloys
,”
Metall. Mater. Trans.
, Vol.
17A
, pp.
115
120
.
27.
Nishida
M.
, and
Wayman
C. M.
,
1988
, “
Electron Microscopy Studies of the ‘Premartensitic’ Transformations in an Aged Ti-51 at.% Ni Shape Memory Alloy
,”
Metallography
, Vol.
21
, pp.
255
291
.
28.
Nishida
M.
,
Wayman
C. M.
, and
Chiba
A.
,
1988
, “
Electron Microscopy Studies of the Martensitic Transformation in an Aged Ti-51 at.%Ni Shape Memory Alloy
,”
Metallography
, Vol.
21
, pp.
275
291
.
29.
Ono
N.
,
Satoh
A.
, and
Ohta
H.
,
1989
, “
A Discussion on the Mechanical Properties of Shape Memory Alloys Based on a Polycrystal Model
,”
Mat. Trans. JIM
, Vol.
30
, p.
756
756
.
30.
Orgeas
L.
, and
Favier
D.
,
1995
, “
Non-symmetric tension-compression behavior of NiTi alloy
,”
J. Phys. IV, Colloq.
, Vol.
5
, p.
605
605
.
31.
Ostuka
K.
,
Wayman
C. M.
,
Nakai
K.
,
Sakamoto
H.
, and
Shimizu
K.
,
1976
, “
Superelasticity Effects and Stress-Induced Martensitic Transformations in Cu-Al-Ni- Alloys,
,”
Acta. Matall.
, Vol.
24
, p.
207
226
.
32.
Patoor
E. A.
,
Eberhardt
and
Berveiller
M.
,
1996
, “
Micromechanical Modeling of Superelasticity in Shape Memory Alloys
,”
J. de Physique
, Vol.
6
, pp.
277
277
.
33.
Perkins
J.
,
1981
, “
Ti-Ni and Ti-Ni-X Shape Memory Alloys
,”
Metals Forum
, Vol.
4
, pp.
153
163
.
34.
Plietsch
R.
and
Ehrlich
K.
,
1997
, “
Strength Differential Effect in Pseudoelastic NiTi Shape Memory Alloys
,”
Acta. Mat.
, Vol.
35
, pp.
2417
2417
.
35.
Shaw
J. A.
, and
Kyriakides
S.
,
1997
, “
On the Nucleation and Propagation of Phase Transformation fronts in a NiTi Alloy
,”
Acta Mat.
, Vol.
45
, pp.
683
700
.
36.
Shimizu, K., Tadaki, T., 1988, Shape Memory Alloys, Funakubo, H., ed., Gordon, and Breach Science.
37.
Sun
Q. P.
,
Hwang
K. C.
, and
Yu
S. W.
,
1991
, “
A Micromechanics Constitutive Model of Transformation Plasticity with Shear and Dilation Effect
,”
J. Mech. Phys. Solids
, Vol.
39
, p.
507
507
.
38.
Sun
Q. P.
, and
Hwang
K. C.
,
1993
, “
Micromechanics Modeling for the Constitutive Behavior of Polycrystalline Shape Memory Alloys-I. Derivation of General Relations
,”
J. Mech. Phys. Solids
, Vol.
41
, p.
1
1
.
39.
Sun
Q. P.
, and
Hwang
K. C.
,
1993
, “
Micromechanics Modeling for the Constitutive Behavior of Polycrystalline Shape Memory Alloys-II. Study of Individual Phenomenon
,”
J. Mech. Phys. Solids
, Vol.
41
, p.
19
19
.
40.
Tobushi
H.
,
Hachisuka
T.
,
Yamada
S.
, and
Lin
P. H.
,
1997
, “
Rotating Bending Fatigue of a TiNi Shape Memory alloy Wire
,”
ICF9 Advances in Fracture Research
, Sidney, Australia, Vol.
3
, pp.
1741
1748
.
41.
Todoroki
T.
, and
Tamura
H.
,
1987
, “
Effect of Heat Treatment after Cold Working on the Phase Transformation in TiNi Alloy
,”
Trans. Jpn. Inst. Met.
, Vol.
28
, No.
2
, pp.
83
94
.
42.
Treppmann
D.
and
Hornbogen
E.
,
1995
, “
The Effect of Dislocation Substructure and Decomposition on the Course of Diffusionless Transformation
,”
J. D. Physique IV
, Vol.
5
, pp.
211
216
.
43.
Treppmann
D.
,
Hornbogen
E.
, and
Wurzel
D.
,
1995
, “
The effect of Combined recrystallization and precipitation processes on the functional and structural properties of NiTi alloys
,”
J. De. Phys.
, Vol.
5
, pp.
569
574
.
44.
Wasilewski
R. J.
,
1971
, “
The effects of Applied Stress on the Martensitic Transformation in NiTi
,”
Metall. Mater. Trans.
, Vol.
2
, pp.
2973
2981
.
45.
Wayman
C. M.
,
1980
, “
Some Applications of Shape Memory Alloys
,”
J. Metals
, Vol.
32
, p.
129
129
.
46.
Wu, M. H., 1988, “Cu-Based Shape Memory Alloys,” Shape Memory Alloys, Funakubo, H., ed., Gordon and Breach Science, pp. 69–88.
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