QUALITY CONTROL PARAMETERS OF THE LASER BEAM HARDENED LAYERS

摘要

The paper analyses the influence of carbon content and of some process parameters on the hardened layer quality by laser beam hardening. At the same steel carbon content, increasing of the laser head advance speed provokes a decreasing both of the layer depth and hardened zone width. For a constant advance speed of the laser head (2 m/min,) a larger hardened zone width from 1.1 mm to 1 25 mm appears, as the carbon concenti-ation grows from 0.25 to 0.55 %. By a constant laser power and at the same carbon content, the surface microhardness increases with 200-400 HV, as the advance speed grows from 1 m/min to 2 m/min after that remains practically constant. The microhardness measurements demonstrated that by increasing of the laser head advancing speed one reduces the laser-material interaction, and by increasing the power over a certain stage some carbide precipitation phenomena occurred.