Determination of a fatigue crack growth law by using Digital Image Correlation
Résumé
The Digital Image Correlation (DIC) was used to identify crack growth law by using Williams expansion series. The identification process was carried out in three steps: (i) determination of displacement fields on each considered load cycle, (ii) determination of the terms of Williams expansion series by minimizing the difference between experimental fields and analytical solutions of Williams [1], and (iii) the coefficients found are used for initialization of the third step, which is an integrated Digitial Image Correlation (iDIC). The procedure enables to get more accurate results than a simple projective method and to decrease the time of identification of the integrated correlation by the initialization with results from the projective method.