Visual Testing (VT) Practice Exam

Weaker structures formed due to external forces over time are’ referred to as what?

1. Corrosive discontinuities

2. Inherent discontinuities

3. Creep

4. Fatigue

The correct answer is: Creep

The term "creep" describes the gradual deformation of materials when subjected to constant mechanical stress over time, especially at elevated temperatures. This phenomenon occurs due to the effects of external forces acting on the material, which can lead to long-term weakening of structural integrity. In the context of materials and engineering, creep is significant because it results in measurable elongation or deformation, indicating how the material is compromised under sustained loads. This can be especially critical in components that operate in high-temperature environments, such as turbine blades or reactors, where the cumulative effects of these external stresses can lead to eventual failure. The other options refer to different phenomena. Corrosive discontinuities are related to the degradation of materials due to chemical reactions, inherent discontinuities are internal flaws present within the material from its formation, and fatigue involves the progressive and localized structural damage that occurs when a material is subjected to cyclic loading. While these concepts are essential in materials science, they do not specifically address the continuous, time-dependent deformation referred to as creep.