A method is suggested for defining the extent of the microplasticity which can exist in a material at stresses between the ‘true elastic limit’ and the nominal yield point or proportional limit.
The suggested mathematical model makes it possible to extrapolate the macroscopic plastic equation into the elastic region in order to take account of the localized nature of the plastic flow.
This analysis can be used to calculate the microplastic hysteresis energy absorbed per cycle by a material under cyclic loading and with a knowledge of the total energy to fracture can be used to predict the number of fatigue cycles to failure; an example is given.
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