Characterisation of microstructural evolution during thermomechanical processing of 15Cr-15Ni-2.2Mo-Ti modified austenitic stainless steel (alloy D9) using ultrasonic measurements

摘要

Ultrasonic attenuation measurements have been used for imaging the variations in the grain size in 15Cr-15Ni-2.2Mo-Ti modified (D9) austenitic stainless steel specimens thermomechanically processed at 1273 K for different strain amplitudes in the range of 0.1 to 0.5. Ultrasonic attenuation measurements could identify various deformation zones such as macroscopic intense shear zones, moderate deformation zones and dead metal zones in the specimen strained to 0.5 exhibiting dynamic recrystallisation. The initiation of the recrystallisation and skew in the loading during the thermomechanical processing could also be identified using ultrasonic attenuation measurements.