Mechanical Engineering: Creep Failure and Design Against Creep

Creep is the time-dependent deformation of a material subjected to a constant ____?

Creep is temperature-dependent and becomes significant when the temperature is greater than ___?

Creep failure occurs when the dimensional change renders the material useless in performing its intended function, such as in creep ____?

Sufficient strain or creep can result in fracture, known as stress rupture or creep ____?

Creep occurs by atomic diffusion, atoms move in response to the applied stress and temperature, to fill the voids in the grains, resulting in an elongation of the grain in the direction parallel to the applied ____?

Creep mechanisms involve a diffusion-controlled process where vacancies in the material’s microstructure migrate toward ____ boundaries.

Creep failures may appear in a ductile or brittle manner.

In a creep test, strain is measured as a function of time at a constant stress and temperature.

Ceramics have a very high resistance to deformation by creep partly because of their characteristically high melting temperatures.

To prevent failure due to creep deformation, it is important to know the operating conditions of the system when selecting materials for an application. Materials experience thermally activated creep at different temperatures.

Dr. Reham Reda Abbas's research involves the assessment of microstructure degradation of creep exposed boiler steels.

Creep is a phenomenon experienced by components in boilers, gas turbine engines, and ovens.

In a creep test, the slope of the strain vs. time curve is the creep rate of the material.

Materials with high melting temperatures are often selected for turbine engine blades to combat the sustained stress over time at a relatively high temperature.

Polymers or tin-lead solder can be susceptible to creep at much lower temperatures compared to nickel-based superalloys.

Rupture lifetime (tr) in a creep test is the total time before failure occurs.