Shielded metal arc, gas tungsten arc, gas metal arc, and submerged arc welding processes were used to provide samples of weld and clad metals of AISI 304 and 347 containing varied amounts of delta ferrite. ASTM A-262 B and E test practices were used to study the general and intergranular corrosion (IGC) behavior under passive conditions. The results showed that delta ferrite was not harmful under passive conditions; on the other hand, it was beneficial in controlling IGC. The corrosion behavior after 650 C heat treatment was influenced by delta ferrite. Electrode polarity also affected corrosion behavior. The IGC mechanism of duplex austenitic stainless steels is applicable.