Product Code: ICAL08_1502

Simulation of Surface Profile Formation in Oxygen Laser Cutting of Mild Steel
Authors:
G.V. Ermolaev, Khristianovich Institute of Theoretical and Applied Mechanics; Novosibirsk Russia
O.B. Kovalev, Khristianovich Institute of Theoretical and Applied Mechanics; Novosibirsk Russia
Presented at ICALEO 2008

A physicomathematical model is proposed for the phenomenon of formation of periodic striations in oxygen laser cutting of mild steel sheets in 3-D case. Mechanism of roughness formation is assumed to be caused by a cyclic reaction of iron-oxygen combustion. The motion of boundaries occurs owing to metal melting under the action of focused laser radiation and the heterogeneous chemical reaction of iron oxidation in oxygen. Mathematical description is based on solving of the adjoint problems of heat and mass transfer in gas, liquid phase and in the solid metal with nonlinear moving interfaces between the substances and states.
Results of numerical simulations of roughness shape and linear size as functions of cutting velocity, and thickness of iron oxide film being formed are presented. Liquid film speed and thickness are obtained from mass and impulse integral conservation. Obtained surface profiles confirm the physical mechanism of roughness formation in oxygen laser cutting of mild steels, which is known from the literature, and are in qualitative agreement with experimental data.