What is the effect of adding hydrogen to the shielding gas mixture in welding?

Adding hydrogen to the shielding gas mixture during welding, particularly for stainless steels, is beneficial as it can increase travel speeds. The presence of hydrogen in the shielding gas helps provide a reducing atmosphere, which can enhance the arc stability and improve the wetting characteristics of the molten pool. This results in a more fluid weld pool, allowing for faster travel speeds without compromising the quality of the weld.

Additionally, hydrogen can contribute to improved penetration and fusion, which are critical when working with stainless steels. This increase in efficiency and speed can be particularly advantageous in applications where reduced cycle times and productivity are important.

While other answers might suggest different effects, the specific benefits of hydrogen integration in the shielding gas for stainless steels highlight why increasing travel speeds is the correct choice.