MECHANICAL TESTING

Surface-Crack Tension Test (SCT) – ASTM E740

This practice is the design, preparation, and testing of a metal sample containing a surface-crack. The ASTM E740 procedure is used to calculate the load-carrying capacity of structural components that have a possible type of flaw. It can also be used for research and development purposes to investigate the failure tendencies of a cracked metal.

This particular standard relates solely to testing under a continuously increasing load however, Touchstone is able to test it under cyclic and sustained loading conditions also.

The test is performed by creating a small semi-elliptical crack in a sample, applying tremendous amounts of increasing pressure to the top of that sample until fracture, and recording the maximum pressure it could withstand before cracking. There is no limit to the strength, toughness, or thickness of the sample. The final calculations include the maximum load withstood and the residual strength.

Reference: ASTM E740 – Standard Practice for Fracture Testing with Surface-Crack Tension Specimens

ASTM E 470

Index of Mechanical Testing