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The presence of hydrogen in steel has long been a concern to many in the metal fabrication industry. The damaging effects of hydrogen are well documented and have been shown to compromise the structural integrity of welds made in susceptible materials such as higher strength steels. Nearly all hydrogen present in the weld and its heat-affected zone is introduced during the fabrication process. Many factors influence the amount of hydrogen found in the welding environment; some can be relatively easily controlled, while others are almost impossible to change. Hydrogen-bearing materials on the surface or combined with constituents in the core of welding consumables are a major source of hydrogen in welding. The environmental exposure (humidity) of these consumables can increase their hydrogen content and can also potentially increase the amount of hydrogen present in the arc environment. Additionally, welding variables such as welding current level (i.e. deposition rate), wire extension, and arc length have also been shown to have an effect on diffusible weld hydrogen levels.

In a number of application areas, such as pipeline construction and fabrication of large cranes and construction equipment, it is common to wait for up to 48 hours before conducting a non-destructive examination of completed weldments for the presence of any cracks or other defects. The theory is that hydrogen diffusion will be most rapid during this time period and that the potential for hydrogen-induced cracking is most likely to occur at this time. This delay in inspection can have a significant negative impact on productivity and can increase manufacturing costs and create production timing and completion issues. The use of a shielding gas supplemented with a gaseous fluoride compound (carbon tetrafluoride, CF4) can potentially reduce these hold times by half or more as diffusible weld hydrogen is significantly lessened in the completed weld. This fluoride addition also has the potential to better control weld hydrogen content which can vary with changing contact tip to work distance and welding arc voltage levels in a production situation.