FAILURE THEORIES(FATIGUE): ANALYSIS AND TYPES

{FAILURE THEORIES/TOF} UNDER FATIGUE LOADING: STUDY AND ANALYSIS

Failure in components under fatigue loading are dealt with the S N curve analysis method.

S N curve in these stress systems plotted with following conditions :

MEAN STRESS(σm) on abscissa (x-axis) and VARIABLE STRESS (σV)/ STRESS AMPLITUDE(σa) ON ORDINATE (y-axis).

THEORIES OF FAILURE ( FATIGUE LOADING):

1)SODERBERG LINE:

*A straight line which joins σe on ordinate (0, σe) to σyt on abscissa (σyt,0) .

*Analysis based on the Yield Strength(σyt) of the material.