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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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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

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Presented by - PRIYANKA MISHRA EI 200199120

SHAPE MEMORY ALLOYS

Martensitic transformation

Deformation of the crystal lattice

Diffusion less Process

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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

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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

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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

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Presented by - PRIYANKA MISHRA EI 200199120

SHAPE MEMORY ALLOYS

DEFORMATION OF MARTENSITE AND RECOVERY TO AUSTENITE

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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

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Presented by - PRIYANKA MISHRA EI 200199120

SHAPE MEMORY ALLOYS

BONE PLATES

DENTAL AND ORTHODONTIC APPLICATIONS

STENT

APPLICATIONS

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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

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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

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Presented by - PRIYANKA MISHRA EI 200199120

SHAPE MEMORY ALLOYS

THANK YOU !!!