Chapter 2 Flashcards
Definition of “Smart Materials”
Materials that are responsive. Often the response is the conversion of one form of energy into another in useful quantities
Definition of “Field-Dependent Materials”
Solids undergo dimensional change (Strain) in response to electric or magnetic fields. Some materials can act as sensors and generate such fields in response to mechanical force.
Name 5 Field-Dependent Materials
- Piezoelectric
- Magnetostrictive
- Electrostrictive
- Electrorheological Fluid
- Magnetorheological Fluid
Definition of “Piezoelectric Materials (PEC)”
materials that can produce electric energy upon application of mechanical stress
Definition of “ Magnetostrictive Materials (MS)”
Materials that can change shape or dimensions during the process of magnetization.
Definition of “Electrostrictive Materials (ESP)”
Materials that can change shape or dimensions during the application of an electric field.
Definition of “Electrorheological Fluids (ERF)”
Materials whose rheological properties, flow and deformation behavior in response to a stress, are strong functions of the electric field strength imposed upon them
Definition of “Magnetorheological Fluids (MR)”
A fluid in a carrier fluid, usually a type of oil. When subjected to a magnetic field, the fluid greatly increases its apparent viscosity, to the point of becoming a viscoelastic solid.
Examples of “Piezoelectric Materials (PEC)”
Zirconate Titanate, cane sugar, quartz, Rochelle salt, and bone
Examples of “Magnetostrictive Materials (MS)”
nickel and alloys such as Fe-Al (Alfer), Fe-Ni (Permalloy), Co-Ni, Fe-Co, and Co-Fe-V (Permendur); several ferrites (CoFe2O4 and NiFe2O4)
Examples of “Electrostrictive Materials (ESP)”
lead magnesium niobate (PMN)
lead magnesium niobate-lead titanate (PMN-PT)
lead lanthanum zirconate titanate (PLZT)
Examples of “Electrorheological Fluids (ERF)”
The additive particles which are mixed in the carrier fluids are mainly polymers, alumina silicates, metal oxides silica.
Various carrier fluids are aldehyde, grease, ketones, kerosene, castor oil, chloroform,
Examples of “Magnetorheological Fluids (MR)”
Ferrous additive usually in mineral oil, silicone oils, kerosene, water
Pros & Cons of “Piezoelectric Materials (PEC)”
perfect for applications that require precise accuracy, such as the movement of a motor but have limited energy outputs, and therefore are potentially cost-prohibitive to feasibly use in any large-scale energy harvesting application
Pros & Cons of “Magnetostrictive Materials (MS)”
Good for actuation and sensing but have bad hysterisis properties and non-linear effects
Pros & Cons of “Electrostrictive Materials (ESP)”
Need cryogenic temperatures and large magnetic fields(Inefficient) but do not need poling or pre-process to be fully operational
Pros & Cons of “Electrorheological Fluids (ERF)”
fast response and easy interface between electrical and mechanical input–output but problem is that ER fluids are suspensions, hence in time they tend to settle out
Pros & Cons of “Magnetorheological Fluids (MR)”
the yield stress of MR fluids is variable which makes it easy to manipulate but a con is the phenomenon called in-use-thickening (IUT), where the fluid is permanently damaged after long-term operation
Definition of Shape-Memory Materials
featured by the ability to recover their original shape from a significant and seemingly plastic deformation when a particular stimulus is applied
2 Examples of Shape-Memory Materials
Shape-Memory Alloys (SMA) & Shape-Memory Polymers (SMP)
Definition & Examples of Smart Glasses
Electrochromic glasses (EC) are glasses that change their transmissivity upon an electrical signal
Susupended-particle- sandwiches suspended, rod-shaped particles between two
transparent layers, which is also opaque until it encounters a current
Definition & Examples of Fiber Optical Sensors
light from a laser or any superluminescent source is transmitted via an optical fiber, experiences changes in its parameters either in the optical fiber or fiber Bragg gratings and reaches a detector which measures these changes.
Temp, Pressure, strain, voltages, etc.
Definition & Examples of Photostrictive Materials
photostriction is the generation of strain by irradiation of light
Polar & non-polar Semiconductors
Name 4 Smart Materials that utilize electric field for both actuation and sensing.
Piezoceramics, piezopolymers, electrostrictors, electrorheological fluids
Name 2 Smart Materials that utilize Magnetic Field for both Actuation and Sensing
Magnetrostrictors
Magnetorheological fluids
Name 4 Smart Materials that Utilize Thermal Energy for both sensing and actuation
Shape Memory alloys, ceramics, polymers, mechanocalories
Name 3 Smart Materials that Utilize Light energy for actuation
Special gels, photostrictors, mechanophotochemics
Name 1 Smart Materials tha utilizes light energy for sensing
fiber optical sensors
Name 2 Smart Materials that utilizes Chemical Energy for actuation
mechanochemics
ionic polymeric gels
Name 1 Smart material that uses Chemical Energy for Sensing
Ionic polymeric gels
Outcome of using Electric Field (2)
Resistance and capacity charge
Outcome of using Magnetic Field (2)
Resistance and Inductance
Outcome of using Thermal Energy (1)
Resistance
Outcome of using Light Energy (1)
Light Intensity
Outcome of Using Chemical Energy (1)
Concentration pH
