Shape Memory Alloys in Biomedicine: Applications in Medical Devices

Question 1

Which of the following properties is NOT characteristic of shape memory alloys?

Accepted Answer

Exceptional electrical conductivity

Answer

Ability to regain original shape after deformation

Answer

Superelasticity and high strain recovery

Question 2

Which of the following is NOT a characteristic property of shape memory alloys (SMAs)?

Accepted Answer

Excellent electrical conductivity

Answer

Ability to return to their original shape after deformation

Answer

Biocompatibility

Answer

High melting point

Question 3

What is the underlying mechanism responsible for the shape memory effect in SMAs?

Accepted Answer

Crystal structure transformation

Answer

Magnetic field alignment

Answer

Thermal expansion

Answer

Plastic deformation

Question 4

Which type of SMA is predominantly used in medical devices due to its superior biocompatibility and low Young's modulus?

Accepted Answer

Nickel-titanium (NiTi)

Answer

Copper-zinc-aluminum (CuZnAl)

Answer

Iron-nickel-cobalt-titanium (FeNiCoTi)

Answer

Gold-platinum (AuPt)

Question 5

What is the primary biomedical application of SMAs in the cardiovascular system?

Accepted Answer

Stents and filters

Answer

Heart valves

Answer

Pacemakers

Answer

Implantable defibrillators

Question 6

In the realm of biomedical research, what promising avenues are being explored for the advancement of shape memory alloys?

Accepted Answer

Enhancing biocompatibility of alloys

Accepted Answer

Discovering new alloy compositions for superior shape recovery

Accepted Answer

Investigating shape memory alloys for drug delivery applications

Question 7

The transformation temperature of an SMA is defined as the temperature at which:

Accepted Answer

The alloy undergoes a phase transformation and recovers its original shape.

Answer

The alloy's shape memory effect is lost.

Answer

The alloy becomes magnetic.

Answer

The alloy melts.

Question 8

The shape memory effect in SMAs is primarily attributed to:

Accepted Answer

A reversible phase transformation.

Answer

Elastic deformation.

Answer

Plastic deformation.

Answer

Annealing.

Question 9

Describe the mechanism underlying the shape memory effect in SMAs.

Accepted Answer

Phase transformation between different crystal structures

Answer

Elastic deformation

Answer

Plastic deformation

Answer

Thermal expansion

Question 10

Which combination of materials is commonly employed in SMAs designed for biomedical applications?

Accepted Answer

Nickel-titanium (NiTi)

Answer

Copper-aluminum (CuAl)

Answer

Iron-manganese (FeMn)

Answer

Gold-platinum (AuPt)

Question 11

Which technique is employed to characterize the shape memory properties of SMAs?

Accepted Answer

Differential scanning calorimetry (DSC)

Answer

Tensile testing

Answer

Magnetic resonance imaging (MRI)

Answer

Microstructure analysis

Question 12

The unique ability of SMAs to return to their original shape after deformation is primarily attributed to:

Accepted Answer

Phase transformation

Answer

Plastic deformation

Answer

Elastic recovery

Answer

Magnetic properties

Question 13

The critical temperature at which an SMA undergoes a phase transformation is known as the:

Accepted Answer

Martensitic start temperature (Ms)

Answer

Austenitic start temperature (As)

Answer

Martensitic finish temperature (Mf)

Answer

Austenitic finish temperature (Af)

Question 14

Which type of SMA exhibits a one-way shape memory effect, meaning it can only memorize and recover one shape?

Accepted Answer

Thermoelastic SMA

Answer

Pseudoelastic SMA

Answer

Ferromagnetic SMA

Answer

Piezoelectric SMA

Question 15

Which factor primarily influences the recovery force exerted by an SMA after deformation?

Accepted Answer

Strain

Answer

Temperature

Answer

Alloy composition

Answer

Grain size

Question 16

The biocompatibility of SMAs for biomedical applications is primarily governed by their:

Accepted Answer

Chemical composition

Answer

Mechanical properties

Answer

Shape memory effect

Answer

Thermal conductivity

Question 17

Which of the following is the defining property of shape memory alloys (SMAs) that enables them for biomedical applications?

Accepted Answer

Capacity to regain original shape after undergoing deformation

Answer

Magnetic susceptibility

Answer

High electrical conductivity

Answer

Low thermal conductivity

Question 18

In biomedical applications, which activation method of SMAs is commonly used for minimally invasive procedures?

Accepted Answer

Thermal activation

Answer

Mechanical activation

Answer

Magnetic activation

Answer

Electrical activation

Question 19

What is the primary responsibility of regulatory bodies in the context of developing and approving SMA-based medical devices?

Accepted Answer

Ensuring safety and effectiveness

Answer

Providing financial assistance

Answer

Establishing design standards

Answer

Conducting clinical trials

Question 20

Which area of research holds significant promise in the field of SMA-based biomaterials?

Accepted Answer

Development of biodegradable SMAs

Answer

Increasing SMA strength

Answer

Enhancing SMA aesthetics

Answer

Reducing SMA cost

Question 21

Which two elements are typically used to form shape memory alloys employed in biomedical devices?

Accepted Answer

Nickel and titanium

Answer

Copper and zinc

Answer

Iron and cobalt

Answer

Aluminum and copper

Question 22

What is the distinctive characteristic of shape memory alloys that allows them to regain their original shape after being deformed?

Accepted Answer

Thermoelastic martensitic transformation

Answer

Plastic deformation

Answer

Superelasticity

Answer

Elastic deformation

Question 23

What is the main advantage of utilizing shape memory alloys in the design of stents?

Accepted Answer

Ability to adapt to complex vessel geometries after deployment

Answer

Lower cost compared to traditional stents

Answer

Reduced risk of blood clot formation

Question 24

In the context of dental braces, how do shape memory alloys contribute to tooth alignment?

Accepted Answer

By applying gentle and continuous force to the teeth

Answer

By releasing medication that stimulates tooth movement

Answer

By providing a rigid structure to hold the teeth in place

Question 25

What is the main advantage of employing shape memory alloys in drug delivery devices?

Accepted Answer

Controlled release of drugs at specific temperatures or locations

Answer

Enhanced solubility of drugs in the alloy

Answer

Reduced risk of drug degradation