CHARACTERIZATION OF ENGINEERING SURFACES BY FRACTAL ANALYSIS

This paper proposes a quantitative evaluation method of fractal surfac e roughness which influences greatly the performance of the surface. T his method is based on the application of fractal geometry theory. The fractal dimension of the profile is obtained by the Fourier transform of the discrete profile data measured by the stylus instrument, The 2 nd and 4th order spectral moments of the profile can be estimated by t he fractal dimension. Then, the surface spectral moments can be also c alculated by the profile spectral moments according to the relationshi p between the surface and the profile spectral moments. By use of thes e parameters, a new method for evaluating surface texture's isotropy i s presented. This method is proved to be useful by the comparison with the experimental results already reported in the past.