Creep in Material property

The slow and progressive deformation of a material with time at a constant stress is called a creep. The simplest type of creep deformation is viscous flow. Depending on temperature., stresses even below the elastic limit can cause some permanent deformation . It is most generally defined as time dependent strain occurring under stress. Metals generally exhibit at creep at high temperature, where as plastics , rubber, and similar amorphous materials are very temperature sensitive to creep.

There are three stages of creep.

In the first one, the material elongates rapidly but at a decreasing rate.

In the second stage, the rate of elongation is constant. In third stage, the rate of elongation increases rapidly until the material fails.

The stress for a specific rate of strain at a constant temperature is called creep strength.

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Mechinopedia For Mechanical Engineers

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