This is a question that comes up frequently when troubleshooting for oxidation in a continuous furnace atmosphere. The rising price of nickel, and therefore stainless steel, has made belt life longevity more important than ever. While many variables—including the belt alloy, initial break-in procedure, wire gauge and tracking—impact the life of a stainless steel belt, you can realize dramatic improvements by adjusting the sintering atmosphere.
Air Products' patented atmosphere process technology has been shown in field service to extend the life of stainless steel belts used in sintering powder metal parts. In general, the atmosphere provides a protective oxide coating on the stainless steel belt while remaining carbon-neutral to your parts. The oxide layer reduces the carbon and nitrogen pickup and helps maintain the desired mechanical properties of the belt. In industry service, the use of this technology has resulted in extending the life of stainless steel mesh belts from 25% to more than 50% over the life that is typically experienced in N₂-H₂ sintering atmospheres. The results of extended belt life: reduced maintenance, less furnace downtime and fewer belts to replace.