A normalization method for life-time prediction of composite materials

The objective of this study is to predict the rupture of specimens of composite materials. During a creep experiment, with traction method, the specimens have different time of rupture (130 seconds, 159 seconds, 539 seconds...). The acoustic activity during the test involves three phases (phase 1, phase 2 and phase 3). When we apply our normalization method (cumulative acoustic emission vs. time), we can notice that all tests look very similar, and we can see that there is a proportionality relation between the transition time $t_{m}$ (phase 1 -> phase 2) and the time of rupture $t_{r}$. The technique works significantly better than other recent works. To validate this technique we have achieved a K-cross validation, on 7 specimens. The proportionality between $t_{m}$ and $t_{r}$ of the 7-cross validations had a mean value of 0.1218 and a standard deviation of 0.0018. The mean errors that we got is about 8.58% ($\pm$ 4.65). It is a very important result in life-time prediction.