Unlike the early grades, these were suitable for welding, allowing the fabrication of large tanks and containers for food and drink production.
Duplex stainless steel provides excellent resistance to a corrosion mechanism called stress corrosion cracking. This happens in environments that combine high temperatures, heavy mechanical loading and environments that contain chlorides – which can happen in food production.
One example is the large tanks that process hot syrup in sugar production. The combination of heat, chlorides in the syrup and the large scale of production can lead to cracks forming in austenitic stainless steels. That’s why duplex stainless steel has been used in these since the 1970s.
Duplex grades are also used widely in hot water systems for breweries, dairies and other facilities.
We are celebrating the 90 years of duplex stainless steel. Duplex stainless steel was originally developed by Outokumpu in Avesta, Sweden in 1930. As the original inventor of duplex we have both experience and expertise to take the material further.