The temperature range in which creep deformation may occur differs in various materials. 7.2 Contributing factors in creep resistivity.4.6.2 Later investigation of the creep region.Therefore, creep is a 'time-dependent' deformation. Instead, strain accumulates as a result of long-term stress. Unlike brittle fracture, creep deformation does not occur suddenly upon the application of stress. For example, moderate creep in concrete is sometimes welcomed because it relieves tensile stresses that might otherwise lead to cracking. Creep is a deformation mechanism that may or may not constitute a failure mode. Creep is usually of concern to engineers and metallurgists when evaluating components that operate under high stresses or high temperatures. Depending on the magnitude of the applied stress and its duration, the deformation may become so large that a component can no longer perform its function – for example creep of a turbine blade could cause the blade to contact the casing, resulting in the failure of the blade.

The rate of deformation is a function of the material's properties, exposure time, exposure temperature and the applied structural load. Creep is more severe in materials that are subjected to heat for long periods and generally increases as they near their melting point. It can occur as a result of long-term exposure to high levels of stress that are still below the yield strength of the material. In materials science, creep (sometimes called cold flow) is the tendency of a solid material to move slowly or deform permanently under the influence of persistent mechanical stresses.

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