Abstract
The concept of a Hausdoeff dimension, so-called fractal dimension, was proposed by Mandelbrot. The application of the fractal dimension provides an effective technique to investigate an irregular morphology. To evaluate the applicability of the fractal analysis in quantitative fractography, a typical fatigue striation formed under several stress ratio on aluminum alloy were analyzed. Fracture surface topography were measured by using an AFM. The fractal dimension used in this study was the correlation dimension. The chaoticity of fracture surface was also evaluated. The results that have been obtained are as follows: (1) Because the maximum Lyapunov exponent becomes a positive number, it is believed that the striation are chaotic. (2) As well as the correlation dimension, it is possible that the maximum Lyapunov exponent becomes a candidate for quantifying the striation topography. (3) Phase diagram are also useful to discriminate the difference in fracture surface.
