A laser-based annealing methodology to speed-up the study of thermo-activated restoration mechanisms in metals.

Abstract

The properties of polycrystalline materials are significantly influenced by annealing treatments. This article introduces a laser-annealing method that facilitates the investigation of high-temperature transformations, with a specific focus on tungsten restoration. The aim of this research is to establish a controlled temperature gradient in the examined sample to expedite the study of restoration at high temperatures by reducing the number of samples. To achieve this, simulations are employed to design the desired temperature profile, and a laser-based setup is adapted to generate and regulate this profile. Furthermore, uncertainties and errors associated with temperature measurements in the experimental setup are quantified. The proposed laser-annealing method enables precise temperature control during the annealing process. By heating one side of a tungsten rod using the laser system, a steady-state temperature gradient is induced. The annealing process consists of two steps: the initial heating phase to reach the desired temperature profile, followed by the maintenance of constant temperatures at specific positions along the rod for a defined duration. The study investigates the impact of absorbed power by the sample on the temperature profile and assesses the softening of tungsten after annealing using hardness measurements. Overall, the proposed laser-annealing method offers a promising avenue for advancing material science research. Its ability to precisely control temperature gradients and observe material behaviors at high temperatures opens up new opportunities to optimize the properties of polycrystalline materials beyond tungsten, thus providing broader applications in material engineering and manufacturing.