J. Zheng et Be. Powell, A METHOD TO REDUCE THE SCATTER IN FATIGUE-CRACK GROWTH-RATE DATA, Fatigue & fracture of engineering materials & structures, 20(9), 1997, pp. 1341-1350
The scatter in experimentally determined fatigue crack growth rates is
dependent, in part, on the data reduction process applied to the pair
ed values of crack length and number of cycles recorded in crack growt
h tests. An additional data reduction process is proposed which replac
es the original test data by a smooth curve. Analysis of mid-range gro
wth rate data for Udimet 720 shows that the introduction of this addit
ional data reduction procedure reduces the scatter in the calculated g
rowth rates, increases the effectiveness of Walker's method in account
ing fbr the effects of stress ratio, and leads to more accurate predic
tions of the experimental crack propagation lives of test specimens.