Study on the influence of scanning strategy parameters on the integrity of the finished product made of Inconel 718 heat-resistant alloy

Sergey Adjamskiy, Ganna Kononenko, Rostyslav Podolskyi, Sergey Baduk

Abstract


Selective laser melting technology, which is an additive manufacturing process, uses a laser beam to fuse metal particles by scanning, following a trajectory according to a given three-dimensional shape based on a CAD model, on the surface of a powder layer. The purpose of the work: the study of the influence of the parameters of the scanning strategy (checkerboard scanning) on the integrity of the finished product made of the heat-resistant Inconel 718 alloy. The task of the research: the development of CAD models and manufacture test samples with dimensions of 10x10x10 mm with manufacturing parameters: power - 80...130 W with a step of 10 W, scanning speed - 850 mm/s, layer thickness - 30 μm; with variable scanning strategy parameters (distance between tracks 0.04...0.09 mm with a step of 0.01 mm); determination of the integrity of test samples was carried out by the metallographic method of research; providing recommendations on scanning strategy parameters to ensure high density finished products. Research methods. Computer modeling, 3D printing using an Alfa-150 printer with Inconel 718 heat-resistant alloy powder, and microscopic studies using an AxioVert 200M Mat optical microscope. Scientific novelty. The influence of manufacturing parameters, namely, power and distance between tracks, on the integrity of the finished product is established. Practical significance. Recommendations for scanning parameters in the manufacture of parts by the method of selective laser melting from heat-resistant alloy Inconel 718 have been developed. Results. The samples have structural defects (pores). Based on the results of the calculations of the specific energy density, it was established that the formation of this defect is connected with the high specific energy at which the manufacturing was carried out. The defects have periodicity and are related to the overlap between the tracks. According to the results of the experiment on the influence of manufacturing parameters in checkerboard order with a layer thickness of 30 microns, it was established that the test samples were printed with the following parameters: speed (850 mm/s), power (80-130 W), distance between tracks (0.04-0, 09 mm) - cannot meet the "satisfactory" rating, and the modes cannot be recommended for the further manufacture of finished products.

Keywords


selective laser melting; scanning strategy; parameters; Inconel 718; energy density.

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DOI: https://doi.org/10.32620/aktt.2025.4sup2.14