Optimal fractal dimension on grain structure robot laser-hardened tool steel

A B S T R A C T A R T I C L E I N F O In order to optimize the structure and properties of tool steel, it is necessary to take into account the effect of the self-organization of a dissipative structure with fractal properties at load. Fractal material science researches the relationship between the parameters of fractal structures and the dissipative properties of tool steel. This paper describes the application of fractal dimension in robot laser-hardening specimens. By using fractal dimensions, changes in the structure can be determined because the fractal dimension is a present indicator of the complexities of the sample forms. We hardened tool steel at different speeds and different temperatures. By researching the fractal dimensions of the microstructures of the hardened specimens we could better understand the effects of the parameters of robot cells on the material. We show the experimental results and an analysis of those fractal patterns that occur during robot laser hardening with the different parameters of temperature and speed. Finally, we present the relationship between the fractal dimensions and the parameters of temperature and speed of robot laser hardening. The hardening of various metal alloys showed that when melting occurs, fractal geometry can be used to calculate the fractal dimension. The dependence of the fractal dimension on the hardness was ascertained. This finding is important when we realize that certain alloys mix poorly because they have different melting temperatures but such alloys have a much higher hardness and better technical characteristics.

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