*3.2. Experimental Validation Based on Melt Pool Geometry Measurement*

In order to predict the morphology of the manufactured part, most of the researchers have used FEA or empirical models [36,37]. The proposed analytical model is used to predict the melt pool size. A comparison between the model and experimental results are conducted. The different process parameters such as laser power and scanning speed are used to predict the melt pool geometry. Figure 13 shows the experimental measurement of melt pool size from Peyre [38]. In this experiment, a high-speed C-Mos camera (Fastcam Photron) is used to measure the melt pool size which is generated by the DMD process.

Figure 14 demonstrates the predicted melt pool size and geometry for different process parameters in metal AM. The laser distance from powder is 1 μm.

**Figure 13.** Experimental measurement of melt pool size for P = 600 W and V = 6 mm/s.

**Figure 14.** Predicted melt pool size in metal AM process for (**a**) P = 600 W, V = 6 mm/s (**b**) P = 360 W, V = 100 mm/s (**c**) P = 300 W, V = 100 mm/s, (**d**) P = 240 W, V = 100 mm/s

As shown in Figure 14, the melt pool depth and length are obtained using the analytical solution of temperature that is given in Section 2.1. The maximum error in length and depth is 7.6% and 3.7%, respectively. Table 4 listed the process parameters, predicted melt pool size, the experimental values, and also the corresponding error. Based on the calculated error, it is shown that the proposed 2D model can accurately capture the melt pool size. As a result, it eliminates the needs for doing costly experiments and also time-consuming FEM.


**Table 4.** Predicted and experimental measurements of melt pool size.
