Fractal-dimension limit of fracture surface in structural steels

This paper presents a method for predicting tile fractal dimensions of duct ile fracture surfaces in structural steels. The fractal dimension of the fr acture surface is a non-monotonic function of the ratio of interparticle sp acing and particle size, and it increases with the increasing: work hardeni ng exponent and the ordering parameter of second-phase particles in the mat rix. The ratio of interparticle spacing and particle size, at which the fra ctal dimension has a maximum, diminishes with increasing work hardening exp onent. The model has been proved for Ni-Cr steel with the structure of temp ered martensite. In the region of stable crack propagation, a very good acc ordance of the experimentally ascertained fractal dimension of the fracture profile with the predicted fractal dimension of fracture surface was found .