Effect of heat treatment after cold rolling deformation of duplex stainless steels SAF 2205

The favorable combination of properties of duplex steels makes this class of stainless steels widely employed in oil and gas, petrochemical, pulp and paper, pollution control, and nuclear industries. They are subjected to precipitation of secondary phases, which degrade the properties in the temperature range 500-1000 degrees C. The aim of this work is to analyze the influence of the heat treatment carried out at 850 degrees and 900 degrees C, in the precipitation of secondary phases after cold rolling deformation (reduction 5%, 10% and 15%). The influence of percent reduction on phase precipitation was analyzed, using optical and electron microscopy. In order to quantify the precipitate phases, the image analysis software was employed. The results revealed that the cold worked material is much more sensitive to precipitation of secondary phases and have consequent weakening after isothermal treatment.