DESIGN, 3D PRINTING AND EXPERIMENTAL STUDY OF PERCOLATIONFRACTAL COMPOSITE STRUCTURAL ELEMENTS

Abstract

The paper presents the results of studies of fractal-honeycomb composite structural elements manufactured by additive 3D printing. The main attention is paid to the study of the influence of the internal fractal structure and the level of filling on the mechanical characteristics of the samples. The research is aimed at determining the relationship between the parameters of internal filling (Q = 10%, 30%, 50%, 100%) and such indicators as mass, density, strength, and bearing capacity of the material. A methodology has been developed for modeling, designing, and calculating fractal structures with regard to operational reliability requirements, which allows the structures to be adapted to different mechanical loading conditions. The created digital models were used for 3D printing of physical samples using a composite filament based on a polymer matrix. A series of experimental compression tests were conducted, which showed a natural increase in the mechanical efficiency of the samples with an increase in the density of the internal filling. The maximum strength values are achieved at full filling, while at lower levels (Q = 10% and 30%) a significant decrease in bearing capacity and a decrease in resistance to deformation are observed. The results confirm that the relative bearing capacity of the samples increases with increasing bulk density, which is critical for the predicted use of structures in critical technical systems. The data analysis also revealed the optimal correlations between the indicators of lightness, strength, and stability, which opens up prospects for further improvement of design solutions. In particular, it is advisable to use fractal-honeycomb composite materials in medicine (orthopedic implants, prostheses), in high-tech engineering, in aerospace and unmanned aerial vehicles, where the parameters of mass and dimensional efficiency are critically important, as well as in the creation of energy-efficient, biocompatible and functionally adaptive engineering systems of a new generation.