Presented By
P.J.ALBERT
RAKESH LAWRENCE
RAPHAEL A VAZHZAPILLY

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DEFINITION
A family of materials with an ability to change few of its original properties by the application of any external stimuli, such as stress,temperature,moisture,ph,electric and magnetic fields are called SMART MATERIALS.
Evolution of smart materials
Most familiar engineering materials and structures until recently have been ‘dumb’
They have been preprocessed and/or designed to offer only a limited set of responses to external stimuli.
‘Dumb’ materials and structures contrast sharply with the natural world where animals and plants have the clear ability to adapt to their environment in real time
The materials and structures involved in natural systems have the capability to sense their environment, process this data, and respond.
Following discoveries lead to the evolution of new kind of materials called smart materials
Shape memory effect
Piezoelectric effect
electrostrictive effect
magnetostrictive effect
electro-rheological (ER) effect.
magneto rheological (MR) effect
Some of the materials which include in this class of materials are
piezoelectric materials,
magneto-rheostatic materials,
electro-rheostatic materials,
thermo-responsive materials,
pH-sensitive polymers,
halochromic materials,
electro chromic materials
thermo chromic materials
photo chromic materials etc
Smart materials are lifeless materials that that assimilate different functions such as sensing, actuation, logic and control to adaptively react to alterations in their environment to which they are exposed, in a constructive and mostly recurring way.
The main advantages of the smart materials are
No moving parts
High reliability
Low power requirements, etc
High energy density (compared to pneumatic and hydraulic actuators)
Excellent bandwidth
Classification of Smart Materials
Actuating Materials
Electrorheological Fluids (ER Fluids)
Shape Memory Alloys (SMA)
Sensing Materials
Fiber Optic (F.O.) sensors
Dual-Purpose Materials (Actuating & Sensing)
Magnetostrictive Materials
Piezoelectric Materials
Piezo electric materials are those materials which generate voltage due to the application of stress.
we find extensive application of piezo electric materials as sensors in different environments.
They are mainly used to measure fluid compositions, fluid density, fluid viscosity, or the force of an impact.
An example from our day to day life would be an airbag sensor in cars, where the piezo electric material senses the force of an impact on the car and sends an electric charge, there by triggering airbag inflation.
Another example of piezo electric material a would be electro-rheostatic and magneto-rheostatic materials, which undergo change in their viscosity.
Electro-rheostatic fluids undergo viscosity change when exposed to an electric field whereas magneto-rheostatic fluids undergo similar changes when exposed to a magnetic field.
Some common electro–rheostatic fluids are milk chocolate or cornstarch, while magneto-rheostatic fluids are minute iron particles suspended in oil.
Thermo-responsive materials such as shape memory alloys or shape memory polymers are smart materials which change their shape with change in temperature.
pH-sensitive polymers enlarge or collapse when they experience change in pH of the surrounding medium
Halochromic materials change their color in response to change in acidity.
Halochromic materials change their color in response to change in acidity.
Electro chromic materials change their color or opacity as a result of the application of voltage, thermo chromic materials change in color based on changes in temperature, and photo chromic materials change their color in response to a change in light.
Photomechanical materials change shape under exposure to light.
Self-healing materials have the intrinsic ability to repair damage due to normal usage, thus expanding the material's lifetime
Dielectric elastomers (DEs) are smart material systems which produce large strains (up to 300%) under the influence of an external electric field.
Shape memory alloys  
Shape memory alloys are metals which exhibit two very unique properties pseudo-elasticity and the shape memory effect
Eg-NiTi(nickel titanium),CuZnAl and CuAlNi
APPLICATION
Fast response valves
High power density hydraulic pumps
Active bearings for reduction of machinery noise
Footwear
Sports equipment
Precision machining
Vibration and acoustic sensors
Dampers, etc.
Healthcare, with smart materials that respond to injuries by delivering drugs and antibiotics or by hardening to produce a cast on a broken limb.
Energy generation and conservation with highly efficient batteries and energy generating materials.
Security and Terrorism Defence with smart materials that can detect toxins and either render them neutral, warn people nearby or protect them from it.
Smart textiles that can change colour, such as camouflage materials that change colour and pattern depending upon the appearance of the surrounding environment. These materials may even project an image of what is behind the person in order to render them invisible.
Surveillance using “Smartdust” and “Smartdust Motes” that are nanosized machines housing a range of sensors and wireless communication devices. Individually they can float undetected in a room with other dust particles. By combining the information gathered from hundreds, thousands or millions of these tiny specs can give a full report on what is occurring with the area including sound and images.
Application of smart materials
There are many possibilities for such materials and structures in the man made world.
Engineering structures could operate at the very limit of their performance envelopes and to their structural limits without fear of exceeding either.
Hence Smart materials would be able to help engineering problems.
These structures could also give maintenance engineers a full report on performance history, as well as the location of defects, whilst having the ability to counteract unwanted or potentially dangerous conditions such as excessive vibration, and effect self repair.

Smart Materials in Aerospace
Some materials and structures can be termed ‘sensual’ devices. These are structures that can sense their environment and generate data for use in health and usage monitoring systems (HUMS).
To date the most well established application of HUMS are in the field of aerospace, in areas such as aircraft checking.
. An aircraft constructed from a ‘sensual structure’ could self-monitor its performance to a level beyond that of current data recording, and provide ground crews with enhanced health and usage monitoring. This would minimize the overheads associated with HUMS and allow such aircraft to fly for more hours before human intervention is required.
Smart Materials in Civil Engineering
They could be used in the monitoring of civil engineering structures to assess durability.
Monitoring of the current and long term behavior of a bridge would lead to enhanced safety during its life.
it would provide early warning of structural problems at a stage where minor repairs would enhance durability,
This would influence the life costs of such structures by reducing upfront construction costs and by extending the safe life of the structure.
Mechatronics
The mechatronic approach is familiar from systems already in existence such as ABS and active ride control in road vehicles,
Piezoceramic bearings to counteract car noise
piezoceramics, a material that transforms electrical energy to motion and conversely dampens vibrations by converting them to electrical energy.
Applications of Smart Nanomaterials
Smart nanomaterials are expected to make their presence strongly felt in areas like
Healthcare, with smart materials that respond to injuries by delivering drugs and antibiotics or by hardening to produce a cast on a broken limb.
Implants and prostheses made from materials that modify surfaces and bio functionality to increase biocompatibility
Security and Terrorism Defence with smart materials that can detect toxins and either render them neutral, warn people nearby or protect them from it.
Aeronautical application
Most aircraft in the air today operates their flaps using extensive hydraulic systems which is very complex and costly to maintain
As piezoelectric fibers ,electrostrictive ceramics and shape memory alloys
Smart wings which incorporate SMA are compact and effecient
Surgical application
Bone plates are surgical tools which are used to assist in the healing of broken and fractured bones
Bone plates can also be fabricated using shape memory alloys in particular nickel titanium
New developments
Optical-fibre crack-monitoring sensors are capable of detecting crack-width up to 5μm. The technologies using smart materials are useful for both existing and emerging technologies.
The technologies using smart materials are useful for both new and existing constructions.
Piezoelectrics for applications were size of the element is of concern. Magnetostrictives are good when size is of no concern
New 'smart' materials are being developed which can alter their properties automatically in response to changes in the environment
Effects such as colour changes can be produced from stimuli such as temperature.
Other 'smart' materials can adapt to their environments in a similar way to plants, with actuators and sensors integrated into structural materials such as concrete and steel, allowing the materials to monitor themselves.
Smart materials to revolutionize manufacturing of products
“Smart materials” process-multiple memory material technology provide engineers with more freedom and creativity by enabling far greater functionality
By this technology SMA can remember multiple different memories each one with different shape
This technology makes smart materials even smarter
Future
The development of true smart materials at the atomic scale is still some way off, although the enabling technologies are under development.
The concept of engineering materials and structures which respond to their environment, including their human owners, is a somewhat alien concept.
ken materials is such a concept.

In future
The development of true smart materials at the atomic scale is still some way off, although the enabling technologies are under development. These require novel aspects of nanotechnology (technologies associated with materials and processes at the nanometre scale, 10-9m) and the newly developing science of shape chemistry.
Worldwide, considerable effort is being deployed to develop smart materials and structures. The technological benefits of such systems have begun to be identified and, demonstrators are under construction for a wide range of applications from space and aerospace, to civil engineering and domestic products. In many of these applications, the cost benefit analyses of such systems have yet to be fully demonstrated.
The Office of Science and Technology’s Foresight Programme has recognised these systems as a strategic technology for the future, having considerable potential for wealth creation through the development of hitherto unknown products, and performance enhancement of existing products in a broad range of industrial sectors.
The concept of engineering materials and structures which respond to their environment, including their human owners, is a somewhat alien concept. It is therefore not only important that the technological and financial implications of these materials and structures are addressed, but also issues associated with public understanding and acceptance.
The core of Yanagida’s philosophy of ken materials is such a concept. This is ‘techno-democracy’ where the general public understand and ‘own’ the technology. Techno-democracy can come about only through education and exposure of the general public to these technologies. However, such general acceptance of smart materials and structures may in fact be more difficult than some of the technological hurdles associated with their development.
Overview of Presentation
Introduction to classification for smart materials and structures
The different materials available
Functionality of smart materials
Uses of smart materials
Advantages and disadvantages of the different materials
Conclusion of preferred application
Smart Materials
Materials that function as sensing and/or actuating materials
Passively smart materials posses self-repairing or stand-by characteristics
Actively smart materials utilize feedback
Smart materials reproduce biological functions in load bearing systems