Midterm 1 Review Flashcards
(11 cards)
Sample Problem: Which of the following smart materials have the slowest response?
Shape Memory Alloy
PZT (Lead-Zirconate-Titanate) (Piezoelectric Ceramic)
MR Fluid
Magneto-strictive material
Shape memory Alloy
They change shape in response to temp changes on the atomic level, taking seconds to minutes.
PZT responds to electrical signals almost instantaneously
MR Fluid changes viscosity in response to magnetic field within milliseconds
Magneto-strictive material change shape in response to magnetic field within milliseconds
Which of the following smart materials has the best linearity:
Shape Memory Alloy
Piezoceramic Material
Electrical-strictive material
magneto-strictive material
Magneto-strictive material
What is TERFENOL-D
Magneto-strictive material - changes shape when exposed to a magnetic field
What is the percentage of material in Nitinol?
50% Nickel and 50% titanium
De-twinning process for a Nitinol SMA actuator happens in what phase?
Martensite
Which of the smart materials has the best bio-compatibility?
NiTi
CuZnAl
CuAlNi
FeNiCoTi
NiTi
Which of the following is NOT true about superelasticity mode of SMA
SMA is deformed above Md (the temperature above which non-elastic deformation is entirely due to plastic yielding)
When material is unloaded, it changes to austenite
SMA is under constant temperature
There is hysteresis in the phase transformation
SMA is deformed above Md is not true
Piezoceramic materials can be used for the following applications, except what
Active vibration control
passive vibration control
high frequency applications
applications involving large deformation or large displacements
Applications involving large deformation or large displacement
For nitinol materials, stress induced martensite result in:
One-way shape memory effect
two-way shape memory effect
Superelasticity
A&B
Superelasticity
The application of MR damper for vibration control of the stay cables on a stay-cable bridge is mainly based on the property of
the materials shape dramatically changes with input voltage
the materials viscosity dramatically changes with input voltage
the materials density dramatically changes with input voltage
the materials electric resistance dramatically changes with input voltage
The materials viscosity dramatically changes with input voltage
MR fluids experience a change in viscosity when exposed to a magnetic field
The application of “vibration control of fighter jet tail vibration using smart structures” is an example of what
Using piezoceramic actuators
shape memory alloy actuators
MR damper
None
Piezoceramic actuators
