An automatic system of handling and heating samples during dynamic hot compression tests

The study describes an innovative system to minimize the effect of thermal gradient in hot compression tests for alloy characterization. The mechanism separates the sample from the tool by using a pneumatic handle with refractory terminals and heats the samples through induction. Once a uniform temperature distribution is achieved, the samples are positioned on the lower punch, and the compressions are performed. Tests on stainless steel validated the efficacy, enabling calibration of Hansel-Spittel constitutive model using Particle Swarm Optimization. Results demonstrate that the innovative system and the data elaboration algorithm improves the precision of flow stress, under several temperatures and strain rates up to 20 s-1. This method can be employed to achieve material calibration, useful for the virtual simulation of the processes with Finite Element Method. This approach offers a robust, cost-effective alternative for material testing in hot plastic deformation processes.