Which gas mixture is commonly used to reduce splatter in the GMAW process?

The mixture of 75% Argon and 25% CO2 is commonly used to reduce splatter in the Gas Metal Arc Welding (GMAW) process due to its favorable characteristics. Argon is an inert gas that helps stabilize the arc and provides a smooth and stable welding process, while the addition of CO2 enhances the arc's ability to penetrate the base material. This balanced mixture helps to control the heat input and improve the fluidity of the weld pool, ultimately leading to a reduction in the amount of spatter produced during welding.

The CO2 also contributes to better arc stability compared to 100% argon, which can sometimes produce a less focused arc depending on the welding parameters used. This combination allows welders to achieve a good compromise between weld bead appearance, penetration, and control over splatter.

Using 100% Argon may provide a clean weld and reduces oxidation but does not effectively mitigate splatter as well as the argon/CO2 mixture. Meanwhile, 50% Argon and 50% O2 could lead to excessive oxidation and potentially increase spatter due to the reactive nature of the oxygen. Lastly, 100% CO2 can create a harsher arc and higher levels of spatter