Fractals Theory Application for Evaluation of Influence of Non Metallic inclusions on Mechanical Properties of S355J2 Steel

Abstract

Influence of non-metallic inclusions in constructional S355J2 steel on mechanical properties has been evaluated by using fractal theory. Since point evaluation of non-metallic inclusions is fault tolerant to mechanical properties change. Point evaluation of experimental steel grades has been evaluated by 1-2 points. Correlation between mechanical properties of the steel (KV20, σ0.2, σB, δ) and fractal dimensions of non-metallic inclusions has been found. Mechanical properties of the steel have been ranking according to influence of fractal dimensions of non-metallic inclusions on the properties. It has been revealed that non-metallic inclusions, evaluated by their fractal dimensions, have strong effect on impact toughness of the steel S355J2 (R² = 0.89). It can be explained by reducing the metal matrix resistance to crack propagation due to non-metallic inclusions in the matrix. Method of mechanical properties ranging by non-metallic inclusions fractal dimensions allow to vary chemical composition of steel for main parameter obtaining. In this particular case for necessary impact toughness of constructional S355 steel narrower chemical composition of the steel should be chosen.

СHARACTERIZATION OF ARC-PVD ZrN NANOSTRUCTURED COATINGS BY USING THE FRACTALS THEORY

“…Therefore, the fractal geometry of B. Mandelbrot [8] makes it possible to give a more differentiated estimation of structures of varying geometric complexity based on value of their noninteger dimension. Fractal formalism is successfully used in modeling the structure and properties of steels [9], cast iron [10], express prediction of the materials hardness [11], estimation of the influence of nonmetallic parts on the mechanical properties of metals [12], ranking the quality criteria of multiparameter technologies [13], etc. The structure of zirconium surfaces is also successfully studied using nonquantitative dimension, which confirms the relevance of choosing a fractal approach in this paper.…”

Fractal Model of Estimating Quality of Cold Worked Fuel Cladding Tubes

“…According to the present-day concepts, surface of many materials is of fractal nature which [4] is the most common case in nature [5]. It may happen that the neglect of fractal dimension [6] of the metal structure elements can introduce an error in establishing a relationship between structure and properties [7].…”