Records |
Author |
Delville, R.; James, R.D.; Salman, U.; Finel, A.; Schryvers, D. |
Title |
Transmission electron microscopy study of low-hysteresis shape memory alloys |
Type |
P1 Proceeding |
Year |
2009 |
Publication |
|
Abbreviated Journal |
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Volume |
|
Issue |
|
Pages |
02005,1-02005,7 |
Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
Abstract |
Recent findings have linked low hysteresis in shape memory alloys with phase compatibility between austenite and martensite. In order to investigate the evolution of microstructure as the phase compatibility increases and the hysteresis is reduced, transmission electron microscopy was used to study the alloy system Ti50Ni50-xPdx where the composition is systemically tuned to approach perfect compatibility. Changes in morphology, twinning density and twinning modes are reported along with special microstructures occurring when the compatibility is achieved. In addition, the interface between austenite and a single variant of martensite was studied by high-resolution and conventional electron microscopy. The atomically sharp, defect free, low energy configuration of the interface suggests that it plays an important role in the lowering of hysteresis. Finally, dynamical modeling of the martensitic transformation using the phase-field micro-elasticity model within the geometrically linear theory succeeded in reproducing the change in microstructure as the compatibility condition is satisfied. Latest results on the extension of these findings in other Ni-Ti based ternary/quaternary systems are also reported. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Edp |
Place of Publication |
Coutaboeuf |
Editor |
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Language |
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Wos |
000274582300009 |
Publication Date |
2009-08-31 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
3 |
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:81951 |
Serial |
3716 |
Permanent link to this record |
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Author |
Salman, O.U.; Finel, A.; Delville, R.; Schryvers, D. |
Title |
The role of phase compatibility in martensite |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of applied physics
T2 – 22nd International Symposium on Integrated Functionalities (ISIF), JUN 13-16, 2010, San Juan, PR |
Abbreviated Journal |
J Appl Phys |
Volume |
111 |
Issue |
10 |
Pages |
103517 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Shape memory alloys inherit their macroscopic properties from their mesoscale microstructure originated from the martensitic phase transformation. In a cubic to orthorhombic transition, a single variant of martensite can have a compatible (exact) interface with the austenite for some special lattice parameters in contrast to conventional austenite/twinned martensite interface with a transition layer. Experimentally, the phase compatibility results in a dramatic drop in thermal hysteresis and gives rise to very stable functional properties over cycling. Here, we investigate the microstructures observed in Ti50Ni50-xPdx alloys that undergo a cubic to orthorhombic martensitic transformation using a three-dimensional phase field approach. We will show that the simulation results are in very good agreement with transmission electron microscopy observations. However, the understanding of the drop in thermal hysteresis requires the coupling of phase transformation with plastic activity. We will discuss this point within the framework of thermoelasticity, which is a generic feature of the martensitic transformation. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4712629] |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000305363700053 |
Publication Date |
2012-05-21 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
11 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.068; 2012 IF: 2.210 |
Call Number |
UA @ lucian @ c:irua:100310 |
Serial |
2919 |
Permanent link to this record |