## 3 Material and Methods  
The experimental processing of the induction heating/warm swaging procedure and the verification of its industrial applicability was a non-negligible part of this study. Schematics of the swaging process, including the initial workpiece, induction heating, swaging, and final swaged piece, are depicted in Figure 5a, whereas the assembly of the real experimental industrially applicable procedure of THAs formation, including the inductor coil, heated workpiece, and swaging head, is depicted in Figure 5b.  
Experimental verifications of the predicted results were performed with 90W7 Ni3 Co workpieces prepared by the UJP Praha a.s. (Prague, Czech Republic) company from a homogeneous mixture of W, Ni, and Co elemental powders, with a minor portion of impurities \(<\) 13 ppm (Fe, Cr, Al, Mo, Ca), by mechanical alloying. The sizes of the powder particles within the final mixture varied between 2 and 4 \(\mu\)m, and the mean particle size was 2.78 \(\mu\)m (Figure 6a). Having mixed the powders, the mixture was consolidated into individual workpieces by CIP (cold isostatic pressing) at 400 MPa, sintered at the temperature of 1525 \({}^{\circ}\)C for 20 min under a protective atmosphere (hydrogen), and eventually cooled down naturally (in furnace). The chemical composition of the sintered pieces was analyzed  
Figure 4: Magnetic field intensity distribution in the 2D model (**a**) and the 3D model (**b**); heat power (Joule heat) distribution in the 2D model (**c**) and the 3D model (**d**).  
Figure 5: Schematics of induction heating and swaging process (**a**); photography of semi-automated laboratory manufacturing line with description of the main features (**b**).  
using a map scan via the SEM-EDX method. In other words, the powder ratios calculated before mixing the powders were verified after sintering via the EDX analysis. The measured area and corresponding acquired spectrum are depicted in Figure 6b,c, respectively. The individual sintered pieces with the approximate length of 330 mm and diameter of 25 mm were subsequently heated to the selected deformation temperatures of 700 \({}^{\circ}\)C, 900 \({}^{\circ}\)C, and 1100 \({}^{\circ}\)C. The maximum heating time given by the industrial requirements was 140 s, whereas the particular deformation temperatures were selected based on our previous experimental studies dealing with the heating of THA workpieces in a conventional electric furnace (e.g., [16; 18]). Temperature control during heating was performed by an optical pyrometer (surface temperature), and verified via implementing two individual K-type thermocouples--one at the surface, and another in the axial region of the workpiece (inserted in an opening pre-drilled via water jet). After pre-heating, the workpieces were swayed to the final diameters of 20 mm. The lengths of the final swaged pieces were approximately 400 mm.  
The microstructure analyses were performed on cross-sectional cuts of the sintered and swaged pieces. The samples were mechanically ground, mechanically polished using the Eposil F substance (Metalco Testing, Prague, Czech Republic), and finally polished using a colloidal silica suspension (VibroMet 2 Vibratory Polisher, Buehler, Esslingen, Germany). Scanning electron microscopy (SEM) analyses (both SEM-EDX and SEM-EBSD) were performed using a Tescan Lyra 3 microscope (Tescan Brno s.r.o, Brno, Czech Republic). The surface quality of the swaged piece was investigated using the innovative 4K digital optical microscopy via the KEYENCE VHX7000 equipment (Keyence International, Mechelen, Belgium).  
Figure 6: SEM-SE image of initial powder mixture (**a**); SEM-SE scan of the area’s chemical composition from which was analyzed (**b**) the element spectrum corresponding to area presented in Figure 6b (c).