ANALYSIS OF METALLURGICAL PHENOMENA IN ISO 5832-9 STEEL SUBJECTED TO HOT TORSION

In the manufacturing of metal alloys, different processing methods are used to achieve desired mechanical properties.Thermomechanical processes involve phenomena such as work hardening (WH), dynamic recovery (DRV), and dynamic recrystallization (DRX), which influence the properties of the materials.However, replicating these processes on a laboratory scale is challenging due to the differences in conditions compared to the industrial scale and the high costs involved.Hot torsion machines are essential tools in simulating these processes, allowing for the study of microstructural evolution and parameter measurements.This article aims to physically simulate thermomechanical processing by hot torsion considering a strain rate of 1.0 s and five testing temperatures.The analytical methods proposed by Poliak-Jonas and Uesugi et al. were used to determine characteristic points of the flow curves and the occurrence of metallurgical phenomena.The alloy used was austenitic stainless-steel ISO 5832-9, which is utilized for orthopedic implants.Results show that temperature has a considerable influence on the shape of the curves, as well as on the DRV and DRX phenomena, which, in turn, are influenced by the stacking fault energy.