Assessment of parameters variations for treatment of CO2 laser carburizing over AISI 4340 steel

摘要

This study evaluated the best parameters for the carburizing treatment using a CO2 laser of low power over an AISI 4340 steel previously subjected to heat treatments of quenching and tempering. The coating process used a liquid dispersion of carbon black in ethanol and carboxyl methylcellulose. The laser power was kept constant at 125 W and the resolution is 600 dots per inch. The variable parameter of CO2 laser was the speed. Two speeds were selected for the coating preparation: 1200 and 2000 m/s. After treatment, metallographic preparation and optical microscopy observation were performed in addition to the evaluation of parameter variations through hardness measurements and microscratch tests.