Exposure to welding fumes causes numerous health problems for many, but a new alloy may reduce the risks considerably. Two Ohio State University engineers have invented a new nickel alloy in an effort to eliminate toxic fumes that threaten the safety of welders. Although the new alloy is more expensive than the ones currently on the market, the benefits may very well outweigh the cost.
Alloy is a welding “consumable,” the material that melts under the welder’s torch and fills the gap between parts being joined. The contents of the fumes depend on the components of the base metal, coatings and/or filling materials, and the temperatures used during welding. The types of metals commonly found in welding fumes are aluminum, beryllium, cadmium oxides, chromium, copper, fluorides, iron oxide, lead, manganese, nickel, vanadium, and zinc oxides. Fumes also produce dangerous gases which can contain carbon monoxide, fluorine, hydrogen fluoride, nitrogen oxide, and ozone.
Gerald Frankel and John Lippold, professors of materials science and engineering at Ohio State, made it their goal to come up with an alloy that produced less toxic fumes. In tests, welds made with the new consumable proved just as strong and corrosion-resistant as welds made with commercial stainless steel consumables. However, when melted the new alloy did not produce fumes of hexavalent chromium, a toxic form of the element chromium which has been linked with cancer. The Ohio State engineers concluded that the consumable alloy that joins stainless steel parts together does not need to contain the metal. Use of the new alloy during welding virtually eliminates the hexavalent chromium in fumes.
The downside of the new alloy is that it’s very expensive. Frankel and Lippold estimate it may cost five to ten times more than standard welding consumables, depending on metal prices. However, Frankel insists the alloy is worth the cost – especially in situations where ventilation is poor. “I always think of someone welding a steel pipe, deep inside a ship at sea,” Frankel explained. “Ventilation might not be possible, and a breathing apparatus for the welder would make working in a confined space even more difficult. In that case, using our alloy would lower the amount of ventilation needed, and help reduce costs overall.”
Ohio State University has issued three U.S. patents and a pending European patent application covering a series of alloys, based on nickel and copper but with no chromium, all of which can be used with standard welding equipment. Frankel and Lippold are currently working to lower the cost of the consumable, and have begun further testing of the alloy with Euroweld, Ltd, a manufacturer of specialty welding materials in North Carolina. Workers will no doubt appreciate the efforts being made to increase safety during welding, and look forward to breathing easier soon.