1：Experimental Design and Method Selection:

The study involved the use of a spectrometer system for in-process monitoring of the LBP DED process. The methodology included the analysis of spectral lines to identify vaporization of chromium and its impact on the material's properties.

2：Sample Selection and Data Sources:

Alloy 718 was used as both the substrate and powder material. The experiments involved depositing single beads of 25 mm length under varying process conditions.

3：List of Experimental Equipment and Materials:

Equipment included a 6 kW YAG fiber laser, a coaxial annular powder nozzle, a powder feeder, a water cooling system, a visible range spectrometer, and an ABB IRB-4400 robot. The spectrometer used was an Ocean Optics (HR2000+) with a 2048 pixel CCD array detector.

4：Experimental Procedures and Operational Workflow:

The process parameters varied included laser power and powder feed rate. Spectroscopic signals were acquired and analyzed offline to evaluate the morphology of the spectra and the recognition of characteristic spectral lines.

5：Data Analysis Methods:

The acquired optical emission spectra were analyzed to identify changes in chromium content, confirmed by Energy-Dispersive X-ray Spectroscopy (EDS) analysis.