Parametric Study of Surface Transformation Hardening with High-Power Lasers

摘要

High-power, continuous-wave CO2 lasers were employed in a parametric study of penetration, cross-sectional area, and hardness in nine steels that provided a wide range in composition, carbon content, hardenability, and response to heat treatment. The test conditions included laser output powers from 5.0 to 12.5 KW and travel speeds in the range 20 to 100 ipm which, with the beam sizes used, resulted in energy densities from 0.52 to 7.01 KJ/sq cm. Laser transformation hardening treatment resulted in appreciable hardness in all the steels that had adequate carbon content and good hardenability. The maximum and average hardness produced in these steels corresponds to martenside contents of 90 to 100 per cent. (Author)