ABSTRACT
In the field of massive and complex manufacturing we are now in need of materials whose properties can be manipulated according to our need. Smart materials are one among those materials. This can change its shape or size by adding little bit of heat. This presentation focuses on smart material such has shape memory alloy and application.
INTRODUCTION
Nature is full of magic materials which are to be discovered in forms suitable to our needs such magical materials also know as intelligent or smart materials can sense, process, stimulate and actuate response. Smart materials have one or more properties that can be dramatically altered. For example: if oil is heated it will become thinner, where as SM with variable viscosity and the fluid which flows easily to solid.
SMART MATERIAL AND THEIR CATEGORIZATION Smart materials Materials that respond with significant
change in a properties upon application of external driving forces-stimuli
“Smart Machines” and “Smart Structures” are composed of smart materials.
Ex of SM: pizoelectric materials, shape memory alloys, Magnetic shape memory, pH- sensitive polymers, photomechanical materials etc.
CATEGORIZATION OF SMART MATERIAL
Based on input and output Based on action/function Based on activation Thermal fields Magnetic fields Electric fields Mechanical fields
SHAPE MEMORY ALLOY’S(SMA) Shape memory can “remember” their shape
when heated above certain transition temperature
Ex: Nitinol & copper- aluminum-nickel.
Shape-memory alloys have different shape-memory effects. Two common effects are one-way and two-way shape memory
Working:
SMA change shape based on a solid state phase transformation and there is change in re arrangement of atoms.
LINEAR MOTION FROM SMA
L1
L1
L2
•SMA at Low temperature
•Stretch the wire a low temperature
•Remove force, new length
•Apply heat, regain original length
cool
hot
Rotational motion is also possible
SHAPE MEMORY EFFECT (2-WAY EFFECT)
Heating Cooling
W
W
W
W
W
W
WORKING OF SMA
TRANSFORMATION OF SMA
heatingcooling
High TemperatureCubic Structure
deformation
Low temperatureDeformed
Low temperatureTwinned monoclinic Structure
AppliedForce
Force removed
Hig
h te
mpe
ratu
reL
ow te
mpe
ratu
re
AsMf
Austenite
Martensite
SHAPE MEMORY ALLOYMEDICAL APPLICATIONS
Orthodontic wire applications
SHAPE MEMORY ALLOY INDUSTRIAL APPLICATION
Greenhouse window systems which close/opendepending on the room temperature
NICKEL-TITANIUM SHAPE MEMORY ALLOYINDUSTRIAL APPLICATION
NiTi eyeglasses frame
NICKEL-TITANIUM SHAPE MEMORY ALLOYINDUSTRIAL APPLICATION
Application of SMAs to an automatic oil-level-adjustment devicein high speed train
APPLICATION IN AIRCRAFT
Location of smart material device used in aircrafts.
1) Propeller
2) Engine monitoring
3) Flutter suppression and Flaps positioning
4) Cabin noise reduction
5) Central control unit
OTHER APPLICATION
Cell phone antenna Eyeglasses Coffee pots Space shuttle
PROBLEMS WITH SMAS Fatigue from cycling
Causes deformations and grain boundariesBegin to slip along planes/boundaries
OverstressA load above 8% strain could cause the SMA to
completely lose its original austenite shape More expensive to manufacture than steel and
aluminum Relatively new
CONCLUSIONS
Smart materials like piezoelectric materials, shape memory alloys, magnetic shape alloy, PH-sensitive polymer, photo mechanical material can be used as actuators for many operation like in aircraft industries, medical industries etc. There fore deeper in site studies can result in better design and development of product
“ smart material can develop smart product”
REFERENCES
Wikipedia.org. Shape Memory Alloys by Marek Novotny. General Applications of Shape Memory Alloys by Dr.Savas
Dlbal. Shape Memory Alloy Research Team Dimitris C.Lagoudas.
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