Abstract
Process parameters are studied for the laser cutting of mild steel plates, whose thicknesses are from 0.8mm to 6mm, by using a small laser machine equipping an 1kW carbon dioxide laser. The ranges of cutting speed and duty are clarified for some plates and the experimental expression is proposed; dc=0.48vt+13, where dc in percentage is the critical value of duty for cutting, v in milli-meter per second is cutting speed and t in milli-meter is the plate thickness. This expression can be applied for the cutting speed over 10 mm/s. Pulse frequency is unrelated factor to the cutting heat input, and then its influence is small on the cutting possibility.
The burning near the kerf is increased with increasing cutting heat input1). When the heat input is the same, the burning is increased with the decrease in duty, resulting in the decrease in the cutting speed. It is increased also with the increase in pulse frequency. The kerf width is increased independently of pulse frequency with heat input at the higher duty.
