This paper investigates aspects of technological damage to structures made using additive technologies, in particular, 3D printing. The main objective of the study is to analyze the effect of printing parameters, in particular the degree of filling, on the mechanical properties of PLA material, which is one of the most popular materials for 3D printing. The paper discusses in detail how the degree of filling of structures, which varies from 20% to 100%, affects their mechanical characteristics, in particular, tensile strength, Young's modulus, and fracture strain. To investigate this, experimental tensile tests were conducted on PLA samples with different percentages of filling. The tests revealed that with an increase in the degree of filling of the structures, the material shows an increase in stiffness and strength, but at certain stages this effect ceases to be linear. The highest values of mechanical characteristics were recorded at 100% filling, but a decrease in the degree of filling led to a significant decrease in the strength of the material, especially at 20% filling, where significant deformation was recorded at lower loads. This indicates a significant influence of the internal structure of the material on its performance, which should be taken into account when designing structures for specific purposes. The obtained results allow us to draw important conclusions regarding the optimization of 3D printing parameters for the manufacture of PLA structures, taking into account the requirements for mechanical properties. Evaluation of the effect of the degree of filling on the parameters of technological damage to the material allows us to develop recommendations for selecting optimal printing conditions depending on the type of product and its intended operating conditions. As a result of the study, the correlation between the mechanical properties of the material and the parameters of 3D printing was determined, which is key to the development of efficient and reliable structures in various fields of application of additive technologies.

PLA, 3D printing, tensile testing, strength, Young's modulus, initial damage, damage parameter

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