3.2.1. Experimental Conditions

The experimental conditions used in this work was follows: the base plates are the stainless steel 304, whose tensile strength was 520 MPa, the diameter of the used welding wire was 1.2 mm, and the material was stainless steel 316L. The shielding gas was composed of 98% pure argon and 2% CO2 (15 L/min flow), the length of wire extension was 12 mm, and flat surfacing welding was used. The size of the base plate was 250 mm × 100 mm × 3 mm. The material characteristics of the base plate and the welding wire was shown in Table 1.

**Table 1.** Material characteristics of the base plate and welding wire.


To accurately reflect the effects of the different operational parameters on the welding quality, the base plate should be carefully preprocessed: the surface has been processed by angle grinder to eliminate the oxides, and then washed by special alcohol. After the surface of base plate was clear and dry enough, the welding action can be taken.
