The Effect of Silicone in Welding Galvanized Steel

About Galvanized Steel

• Because of its durability and malleability, steel is used extensively to make products for commercial and industrial uses. Steel undergoes a chemical reaction in the presence of moisture, however, leading to rusting that deteriorates the material over time. Galvanization uses zinc oxide to coat the steel, giving the material much more resistance to this corrosion. The galvanizing process may use either hot dipping or cold dipping of the zinc oxide compound. In hot dipping, steel is placed in molten zinc at a high temperature. The zinc then reacts with oxygen in the air to create zinc oxide, a dull-gray layer that resists rusting. Cold-dip galvanizing is not really galvanizing but coating with a zinc-rich paint that provides some rust protection, though not as much hot dipping provides.

Silicon Composition of Steel Materials

• The composition of the steel can have a significant effect on the galvanizing process. Differences in silicon levels can create a different appearance of the galvanized surface, according to the GalvanizeIt website. The galvanizing process can also cause problems with welding. The zinc coating can increase spatter formation and decrease weld penetration. Using a silicon spatter-reducing compound can help limit these problems. Sometimes, however, the zinc coating may have to be ground off to produce a solid joint between pieces of the galvanized material.

Welding Galvanized Steel

• Several different welding methods can be used for galvanized steel, including gas metal arc welding, oxyacetylene, stud welding and friction welding. Though in most cases, simple mild steel wire is used to create the joint, adjusting the voltage and current of the welding equipment can help to create better welds on galvanized material.

Silicon Bronze Welding Rod

• Many of the problems of welding galvanized steel products can be minimized by the use of brazing techniques with alloy rods. Using a 3 percent silicon bronze rod can increase the fluidity of the puddle, reduce spatter and prevent the cracking that is common with galvanized materials, according to the Fabricator website.

Precautions When Welding Galvanized Steel

• Welding galvanized steel with silicon bronze or any other type rod should always be done in a well-ventilated area to minimize fumes from the zinc coating. These fumes can have serious effects on the health of the welder, including respiratory problems and flu-like symptoms.