1：Experimental Design and Method Selection:

Laser welding was performed using a CO2 laser (LC-ALPHAIII) with pulses at high frequencies. The focusing lens had a 127 mm focal length, resulting in a spot diameter of 0.8 mm on the sample surface. Nitrogen assisting gas was used to prevent high temperature oxidation reactions.

2：8 mm on the sample surface. Nitrogen assisting gas was used to prevent high temperature oxidation reactions. Sample Selection and Data Sources:

2. Sample Selection and Data Sources: Workpieces were prepared from sheets of steel SAISI 304, Ti6Al4V, and Inconel 625 alloy with dimensions 1000 × 50 × 2.5 mm3. Experiments were repeated twelve times to achieve a confidence level of 94%.

3：5 mmExperiments were repeated twelve times to achieve a confidence level of 94%. List of Experimental Equipment and Materials:

3. List of Experimental Equipment and Materials: CO2 laser (LC-ALPHAIII), optical microscope, Jeol 6460 electron microscopy, Bendix stylus instrument.

4：Experimental Procedures and Operational Workflow:

The laser output was set to pulses at 1200 pulses/second. The welding parameters included a welding speed of 10 cm/s, power of 2000 W, frequency of 1200 Hz, nozzle gap of 1.5 mm, nozzle diameter of 1.5 mm, focus setting of 127 mm, and N2 gas pressure of 550 kPa.

5：5 mm, nozzle diameter of 5 mm, focus setting of 127 mm, and N2 gas pressure of 550 kPa. Data Analysis Methods:

5. Data Analysis Methods: The energy consumption and the size of the welded sections were formulated using the lump parameter analysis. The weld widths were recorded using the optical microscope, and the mass loss from the top surface of the welded specimens was determined using Jeol 6460 electron microscopy.