## 4 Results  
### Induction Heating, Prediction vs. Experiment  
Having verified the Forge NxT 3D model by comparing the results of the electromagnetic computations with the result acquired from the ANSYS Maxwell 2D model, the induction heating was simulated in 3D space only. The transient tasks were defined in accordance with the above-characterized results of the electromagnetic analyses. The aim of the simulations was to identify the optimum inductor power output for the heating of the WNiCo workpieces before swaging. In order to minimize the processing time and reduce/eliminate the possible occurrence of microstructure/surface changes, the maximum heating time was limited to 140 s. The temperature development was observed in two individual locations within the workpiece with the required conditions to achieve the target temperature in all the measured locations within the given heating time. Figure 7a,c,d depict the developments of temperatures as dependent on heating time for two individual locations within the heated workpiece--on its surface and in the longitudinal axis (schematic depictions of the measured locations are depicted on the longitudinal cut through the workpiece in Figure 7b)--during heating, using the currents of I = 70, 90, and 120 A, to the target deformation temperatures of 700 \({}^{\circ}\)C, 900 \({}^{\circ}\)C, and 1100 \({}^{\circ}\)C, respectively. The mentioned figures show that the courses of the curves for the modeled variants differed significantly. The smallest temperature gradient between the surface and axial regions of the WNiCo workpiece was observed for the current of 70 A, i.e., the target temperature of 700 \({}^{\circ}\)C (Figure 7a). Increasing the target heating temperature then resulted in increasing the observed temperature gradient across the workpiece. On the other hand, despite the fact that the temperature of 700 \({}^{\circ}\)C was reached in both the monitored locations throughout the workpiece within the required heating time of 140 s, the heating regime selected for the target temperature of 700 \({}^{\circ}\)C did not introduce the required decrease in the flow stress, i.e., an increase in plasticity before subsequent swaging, as further demonstrated. The results of the prediction of the temperature distribution within the WNiCo workpiece heated to the target temperature of 900 \({}^{\circ}\)C (current of 90 A) document that the bulk of the workpiece exhibited the minimum required temperature of 900 \({}^{\circ}\)C already after 130 s of heating (Figure 7b,c). The maximum predicted gradient between the workpiece surface and axial temperatures during heating was lower than 100 \({}^{\circ}\)C. Figure 7d then depicts the development of temperatures within the workpiece during induction heating to the temperature of 1100 \({}^{\circ}\)C, i.e., with the current of 120 A. This heating regime imparted intriguing temperature behavior; at the beginning of heating, increases in temperature in the axial workpiece region were evidently delayed compared to the temperature in the surface region, which was relatively quick from the beginning and during the entire heating process. The figure also shows that the target heating temperature was achieved already before the maximum heating time of 140 s. Nevertheless, the predicted temperature gradient during heating is unfavorable, since, especially at the beginning of heating, temperature differences across the workpiece can result in the development of cracks and defects. Additionally, other phenomena, such as the quick oxidation of the surface, start to occur. For this reason, the temperature regime with the target temperature of 900 \({}^{\circ}\)C was selected as optimal from the viewpoint of heating time vs. achieved temperature, as well as from the viewpoint of predicted temperature gradient.