Microstructural changes occurred during hot-deformation of sdss f55 (Super-duplex stainless steel) alloy

The paper aims to study the effects induced by thermomechanical processing on the microstructural evolution of the Super Duplex Stainless Steel F55 (SDSS F55). The experimental investigations involved five samples, of identical dimensions, hot deformed at temperatures between (800°C-1100°C). All samples were deformed by the dead-weight drop method at the same potential energy. The microstructural features of SDSS F55 alloy induced by hot deformation were analyzed using scanning electron microscopy (SEM). The results showed that initial sample presented two stable phases (ferrite (δ) and austenite (γ)), while hot deformation at a temperature between (800°C-1000°C) induces the appearance of the deleterious sigma (σ) and chi (χ) phases. It was observed that the sigma (σ) and chi (χ) phases are disappearing at hot deformation temperatures above 1000°C. © 2019, Politechnica University of Bucharest. All rights reserved.