OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 26 No. 4 2024 Four types of specimens were printed during the experimental work. Vertically and horizontally orientated specimens of each of the investigated technologies (EBAM and WAAM) were made. Cross sections of the specimens were made to investigate the microstructure. The microstructure was revealed using an etchant consisting of a mixture of concentrated nitric HNO3 (67 wt. %) and hydrochloric HCl (33 wt. %) acids taken in a ratio of 1:3 by volume. Microstructural studies were carried out using a metallographic microscope MMP-1 manufactured by BIOMED. Photographs of the microstructure were obtained using a DCM-510 SCOPE video eyepiece. Microhardness was measured using an automatic complex based on the EMCO-TEST DuraScan-10 microhardness tester. The measurements were carried out on the same specimens on which metallographic studies were carried out. Measurements were carried out with a Vickers indenter at a load of 1 kgf with a dwell time of 10 s. Results and discussion First of all, specimens were obtained for the research. Four specimens were obtained, two specimens using each of the EBAM and WAAM technologies. Specimens of vertical orientation (Figure 1 a, c) and horizontal orientation (Figure 1 b, d) were obtained. From the above pictures, it can be seen that the accuracy and surface quality of the specimens obtained by EBAM is higher. There is less metal spatter than when surfacing using an arc. Also, the cooling rate of specimens obtained by EBAM is lower than with WAAM printing. With EBAM, heat dissipation is diffi cult due to the lack of atmosphere. In WAAM surfacing of Inconel, helium is used. In addition, it is evident that the EBAM specimen has a greater number of layers. In WAAM surfacing, the thickness of printed layer is greater and the printing speed is higher. But this is accompanied by signifi cant temperature fl uctuations. The stresses caused by these temperature fl uctuations cause deformation of the substrate, even when it is about 5 mm thick. In this case, vertical orientation of the specimens gives a higher speed, but at the same time higher stresses arise. With horizontal orientation, the specimen cools down more uniformly. This is refl ected in a less deformation of the substrate. Ta b l e 1 Chemical composition of Inconel 625 nickel alloy wire Chemical element Ta Al Nb Mo Cr Si Fe Co Ti Mn Ni % 0.3 0.38 2.8 7.5 22.5 0.8 1.3 0.2 0.35 0.1 63.68 a b c d Fig. 1. Photos of specimens obtained using various additive technologies: a – horizontal specimen obtained using EBAM technology; b – vertical specimen obtained using EBAM technology; c – horizontal specimen obtained using WAAM technology; d – vertical specimen obtained using WAAM technology
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