Hello aerowelder, Chuck Meadows is a gentleman who frequents the forum regularly and could likely answer that for you as well as a number of others. If you don't get a response on here fairly soon try sending a PM to him. Regards, aevald

The only time a duplex steel is to receive a heat treatment is when it is a solution anneal temperature, 1100-1150C. This is normally done when the duplex is suspected of having detrimental intermetallic phases. Otherwise, a post weld heat treatment is not recommended or necessary.