A Comprehensive Study on Texture Development and Twin-Related Domain Evolution Following Hot Compression in a Super Austenitic Stainless Steel

摘要

Uniaxial hot deformation was carried out in a wide range of temperatures (1173 K to 1423 K) and strain rates (0.001 to 10 s(-1)) in a super austenitic stainless steel employing a Gleeble thermomechanical simulator. The evolution of fine grains due to dynamic recrystallization (DRX) with near-random texture was evident following deformation at strain rates 0.001 to 10 s(-1) and temperatures 1173 K to 1273 K. The deformed grains in this domain exhibited the typical formation of < 110 & rang;//ND or alpha fiber, and its volume fraction gradually increased when the resistance to deformation increases. Weak deformation texture was persisted in the fine DRX grains (<= 3 mu m) which gradually converted to a strong < 001 & rang;//ND fiber following grain growth. The deformation texture was simulated by employing a crystal plasticity finite element method (CPFEM). The texture inhomogeneity was observed in the typical compressed specimen which was associated with variation in stress/strain paths at different locations of the hot compressed specimen. Further, the n-ary sumation 3 twin boundary evolution was analyzed employing Pande's relationship and twin-related domains (TRDs) analysis. The growth accident was identified as the major mechanism of n-ary sumation 3 twin boundary evolution during DRX in this alloy. Moreover, the n-ary sumation 3 regeneration was also evident in a small domain of hot working (1323 K/0.001 s(-1)) which was substantiated by texture randomization and formation of relatively larger TRDs in the microstructure.