Podcast
Questions and Answers
Creep is the time-dependent deformation of a material subjected to a constant __________, usually less than the yield stress.
Creep is the time-dependent deformation of a material subjected to a constant __________, usually less than the yield stress.
False
Creep is also __________-dependent, it is only significant when the temperature is greater than 0.4 Tm.
Creep is also __________-dependent, it is only significant when the temperature is greater than 0.4 Tm.
False
A material experiences creep failure when the dimensional change renders the material useless in performing its intended function, such as in creep __________.
A material experiences creep failure when the dimensional change renders the material useless in performing its intended function, such as in creep __________.
False
Sufficient strain or creep can result in __________, known as stress rupture or creep fracture.
Sufficient strain or creep can result in __________, known as stress rupture or creep fracture.
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Creep occurs by atomic __________, atoms move in response to the applied stress and temperature.
Creep occurs by atomic __________, atoms move in response to the applied stress and temperature.
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Vacancies in the material’s microstructure migrate toward grain boundaries in a diffusion-controlled _________.
Vacancies in the material’s microstructure migrate toward grain boundaries in a diffusion-controlled _________.
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Creep failures can appear in a ductile or brittle manner. True or False?
Creep failures can appear in a ductile or brittle manner. True or False?
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Materials with high melting temperatures are often selected for applications like gas turbine engines due to ___________.
Materials with high melting temperatures are often selected for applications like gas turbine engines due to ___________.
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Ceramics have a very high resistance to deformation by creep due to their ___________.
Ceramics have a very high resistance to deformation by creep due to their ___________.
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In a creep test, a constant ________ stress is applied to a specimen maintained at a constant temperature.
In a creep test, a constant ________ stress is applied to a specimen maintained at a constant temperature.
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The slope of the strain vs. time curve in a creep test is the __________ of the test or the creep rate of the material.
The slope of the strain vs. time curve in a creep test is the __________ of the test or the creep rate of the material.
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Rupture lifetime (tr) in a creep test is the total ________.
Rupture lifetime (tr) in a creep test is the total ________.
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The thermal activation of dislocations is required to move pinned dislocations during ________.
The thermal activation of dislocations is required to move pinned dislocations during ________.
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Boilers, gas turbine engines, and ovens are examples of components that experience ________ phenomenon.
Boilers, gas turbine engines, and ovens are examples of components that experience ________ phenomenon.
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To prevent failure due to creep deformation, it is important to know the operating conditions of the system when selecting materials for an application. True or False?
To prevent failure due to creep deformation, it is important to know the operating conditions of the system when selecting materials for an application. True or False?
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Vacancies migrate along grain boundaries and dislocations move (climb) to accommodate the applied stress in the form of ________ during creep.
Vacancies migrate along grain boundaries and dislocations move (climb) to accommodate the applied stress in the form of ________ during creep.
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