CPT Materials, Tools, & Safety in Prosthetics 5

Question 1

Which thermoset resin system is most often used for definitive prosthetic socket lamination due to its low shrinkage and high strength?

Accepted Answer

Epoxy resin

Answer

Epoxy resin offers low cure shrinkage, excellent mechanical properties, and strong adhesion to reinforcing fibers, making it the preferred choice for definitive sockets.

Question 2

What does the term 'fiber volume fraction' describe in a composite laminate?

Accepted Answer

The proportion of the composite cross-section occupied by reinforcing fibers

Answer

Fiber volume fraction is the ratio of fiber cross-sectional area to total composite cross-sectional area and directly influences mechanical performance.

Question 3

When storing isocyanate-based materials (polyurethane components) in a prosthetics lab, which condition is MOST critical to maintain?

Accepted Answer

Low humidity and sealed containers

Answer

Isocyanates react vigorously with moisture; storage in sealed containers at low humidity prevents premature reaction and degradation of the material.

Question 4

A technician must grind titanium components. Compared to grinding steel, titanium grinding requires:

Accepted Answer

Lower wheel speed, sharp abrasives, and cooling fluid

Answer

Titanium's low thermal conductivity causes heat buildup; lower wheel speed, sharp abrasives, and coolant prevent work hardening and fire risk from titanium sparks.

Question 5

Which test method is used to evaluate the peel strength of an adhesive bond between two prosthetic components?

Accepted Answer

T-peel test (ASTM D1876)

Answer

The T-peel test measures the force required to peel apart two bonded flexible substrates, directly quantifying adhesive peel strength.

(CPT) Certified Prosthetic Technician Practice Test

(CPT) Certified Prosthetic Technician Practice Test

CPT Materials, Tools, & Safety in Prosthetics 5