What can happen if hydrogen levels are too high in the gas mixture when welding?

When hydrogen levels are too high in the gas mixture during the welding process, it can lead to porosity in the weld. Porosity refers to the presence of small gas pockets or voids in the weld metal, which can significantly weaken the overall strength and integrity of the weld. High hydrogen levels can cause the gas to dissolve in the molten metal, and as the weld cools, this trapped hydrogen can form bubbles that do not escape, resulting in these undesirable voids.

The formation of porosity can compromise the mechanical properties of the weld and make it more susceptible to failure under stress. This is especially crucial in applications where structural integrity is paramount. Therefore, controlling the levels of hydrogen in the shielding gas mixture is vital to preventing porosity and ensuring high-quality welds.