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You should be able to answer these questions without too much difficulty after studying this TLP. If not, then you should go through it again!
Which of the following could be reasons tertiary creep is observed?
In the γ/γ' structure of Ni-based superalloys, why is the existence of a coherent interface important?
What is the function of the recess in Indentation Creep Plastometry?
The following questions require some thought and reaching the answer may require you to think beyond the contents of this TLP.
Why is creep deformation different from conventional deformation?
A. Incorrect. For conventional deformation any strain is produced instantaneously as a result of a change in applied stress.
B. Correct. Creep differs from conventional plastic deformation because it is time-dependent deformation.
C. Incorrect. Creep can occur, regardless of absolute temperature, provided the homologous temperature is above (roughly) 0.4
D. Incorrect. The creep strain rate is proportional to applied stress raised to the stress exponent.
Which of the following statements is true?
D. All creep mechanisms tend to be controlled by diffusional processes, which explains why creep deformation is time-dependent – it takes time for atoms to diffuse a given distance."
Which of the following is not an assumption that we make during the creeping coil experiment?
A. Because the deformation occurs via torsion there is no reduction in cross sectional area and hence, although we are under constant load, we are also under constant true stress conditions
Which of the following features of Ni superalloy turbine blades helps to make them resistant to creep? (There may be more than one)