Original paper(Vol.48 No.9 pp.1003)

Metallo-thermo-mechanical simulation of traveling CO sub 2 laser quenching process of a carbon steel

Nakasaki Kazuyuki; Inoue Tatsuo

Abstract:Thin CO2 laser beam system is applied to the line-quenching process of a carbon steel block under traveling heat condition. Since it is very difficult to experimentally evaluate the temperature variation, characteristic property of laser irradiated zone and residual stresses during and after the operation, especially, in heat traveling condition, numerical simulation by finite element simulation code 'HEARTS' is implemented based on metallo-thermo-mechanics developed by the authors. The results of the simulated stress distribution seem to represent the practical mode of tensile and compressive stresses after quenching, and characteristics of the martensite transformed region is compared with the observed micrograph in cross section of the block. Stress distribution and volume fraction of martensite of the edge of starting and finishing the beam reveal to differ from the data at the intermediate part. Some numerical simulation is carried out to evaluate the effect of operating condition.

Key Words:laser-quenching, CO2 laser, surface hardening, heat traveling condition, metallo-thermo-mechanics, finite element method