Engineering Board Exam Reviewer · Engineering Materials · medium
The fracture surface of a fatigue failure typically shows:
- A cup-and-cone shape
- Beach marks (clamshell marks) radiating from the crack origin
- Uniform shiny facets only
- Necking
Answer
B. Beach marks (clamshell marks) radiating from the crack origin
Solution
Cup-and-cone fracture is typical of ductile tensile failure.
More Engineering Materials questions
- Welding of high-carbon steels is difficult mainly because:
- Powder metallurgy involves:
- Hot working is performed:
- Cold working a metal generally:
- Steel has E = 200 GPa and = 7.85 g/cm3; aluminum has E = 70 GPa and = 2.70 g/cm3. Which has the higher specific stiffness (E/ )?
- Heat flows through a 100 mm thick polystyrene insulation panel (k = 0.05 W/m· K) of area 10 m2 with a temperature difference of 30 °C…
- An aluminum rod (E = 70 GPa, = 23.6 × 10-6 /° C) is held between rigid supports and heated by 80 °C. What compressive thermal stress…
- An aluminum bar 2 m long is heated by 80 °C. How much does it expand? ( = 23.6 × 10-6 /° C)
- An n-type silicon sample has 1 × 1022 free electrons per m3 with an electron mobility of 0.14 m2/V· s. What is its electrical…
- Copper has an electrical resistivity of 1.72 × 10-8 · m. What is its electrical conductivity?