A Study on Monitoring Technology for Improving the Efficiency of Metal 3D Printing

In this study, a process monitoring approach was developed to collect and analyze in-situ data during the Ti64ELI laser powder bed fusion (PBF) process. Real-time images of each layer and corresponding energy mapping data were obtained using a built-in high-speed camera system. The results demonstrated that excessive heat input regions, observed as red dots in energy maps, were associated with over-melting and structural collapse in the upper layers. Mechanical testing of six specimens fabricated under identical process parameters (laser power: 450 W, scan speed: 1,500 mm/s, layer thickness: 50 ㎛) showed average yield strength of 906 MPa, ultimate tensile strength of 997 MPa, and elongation of 12.3%, consistent with the typical range for Ti64ELI additively manufactured alloys. However, specimens with locally concentrated energy input exhibited reduced elongation due to uneven heat distribution. These results confirm that energy distribution and geometric instability during the AM process have a significant effect on mechanical properties. The captured layer-wise images and energy mapping data were studied as monitoring technology capable of analyzing defects that may occur during the process and predicting quality in the 3D printing process.