Tech
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Presented by - PRIYANKA MISHRA EI 200199120
SHAPE MEMORY ALLOYS
Technical Seminar Report On
“SHAPE MEMORY ALLOYS”
under the guidance ofMr. VIVEK SHARMA
submitted by
PRIYANKA MISHRA EI200199120
Tech
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Pre
senta
tion 2
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4
Presented by - PRIYANKA MISHRA EI 200199120
SHAPE MEMORY ALLOYS
INTRODUCTION
Shape memory alloys are metals that “remember” their original shapes.
Key characteristic - Martensitic phase transformation
SHAPE MEMORY ALLOYS
The two unique properties•shape memory effect•pseudo-elasticity
Tech
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Pre
senta
tion 2
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4
Presented by - PRIYANKA MISHRA EI 200199120
SHAPE MEMORY ALLOYS
Martensitic transformation
Deformation of the crystal lattice
Diffusion less Process
Tech
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Pre
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tion 2
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Presented by - PRIYANKA MISHRA EI 200199120
SHAPE MEMORY ALLOYS
Shape Memory Effect
The transformation begins in the absence of stress, at a temperature M0s
The transformation continues as the temperature is lowered until a temperature M0f
The reverse transformation begins at the temperature A0s
and at the temperature A0f the material is fully austenite
Tech
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Pre
senta
tion 2
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4
Presented by - PRIYANKA MISHRA EI 200199120
SHAPE MEMORY ALLOYS
Pseudo-elasticity
pseudo-elasticity occurs without a change in temperature
Transformation occurs upon loading and unloading
Rubber like effect
Tech
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Pre
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tion 2
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Presented by - PRIYANKA MISHRA EI 200199120
SHAPE MEMORY ALLOYS
STRESS-TEMPERATURE RELATIONSHIP
Stress plays an important role in the Transformation
An applied stress increases the Transformation Temp
TRANSFORMATION TEMPERATURES
The temperature at which the material transforms from Martensite to Austenite is controlled by alloy composition
Tech
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Pre
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tion 2
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Presented by - PRIYANKA MISHRA EI 200199120
SHAPE MEMORY ALLOYS
DEFORMATION OF MARTENSITE AND RECOVERY TO AUSTENITE
Tech
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Presented by - PRIYANKA MISHRA EI 200199120
SHAPE MEMORY ALLOYS
TRAINING OF SMA
The wire is hot/cold worked when it is in the Martensite phase
The wire is then heated to Af to recover its shape.
The wire is then cooled to martensite.
Effect-The solid exhibits two stable shapes
Tech
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Presented by - PRIYANKA MISHRA EI 200199120
SHAPE MEMORY ALLOYS
BONE PLATES
DENTAL AND ORTHODONTIC APPLICATIONS
STENT
APPLICATIONS
Tech
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Pre
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Presented by - PRIYANKA MISHRA EI 200199120
SHAPE MEMORY ALLOYS
ADVANTAGES AND DISADVANTAGES OF SHAPE MEMORY ALLOYS
ADVANTAGES
•Bio-compatibility
•Diverse field of application
•Good mechanical properties
DISADVANTAGES
•Expensive
•Poor fatigue properties
Tech
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Pre
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tion 2
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Presented by - PRIYANKA MISHRA EI 200199120
SHAPE MEMORY ALLOYS
CONCLUSION
A shape memory effect can undergo plastic deformation, and then be triggered into returning to its original shape
Led to a proliferation of diverse application
Tech
nic
al Sem
inar
Pre
senta
tion 2
00
4
Presented by - PRIYANKA MISHRA EI 200199120
SHAPE MEMORY ALLOYS
THANK YOU !!!