1：Experimental Design and Method Selection

The study involved instrumenting a laser welding machine to measure different quantities using various optical diagnostics tools.

2：Sample Selection and Data Sources

316L stainless steel plates and 15CDV6 low alloy steel plates were used for laser welding tests. For the melting of a powder bed, a hollow 316L substrate was filled with a layer of 316L powder.

3：List of Experimental Equipment and Materials

High-speed camera, infrared camera, pyrometer, optical microscope, DRC machine, 3D measuring arm, TRUMPF LASMA 1054 CNC machine, PRECITEC YC52 laser head, LASERLINE LDM 3000-60 diode laser, Phantom VEO 710 high-speed camera, FLIR Phoenix MWIR infrared camera, KLEIBER LVO 25 S-7 monochromatic pyrometer, PROTO DRX machine, FARO GAGE 3D measuring arm.

4：Experimental Procedures and Operational Workflow

Laser welding tests involved creating a bead on each sample with varying speeds. The melting of a powder bed involved filling a substrate with powder and then melting it using a laser. Measurements were taken for molten pool morphology, temperature field, residual stresses, and distortions.

5：Data Analysis Methods

The length and width of the weld pool were measured from images of the high-speed camera. The depth and height were determined using an optical microscope. Temperature distribution was obtained using an infrared camera and pyrometer. Residual stresses were measured using a DRX machine, and distortions were measured using a 3D measuring arm.