Gas-Jet Laser Cutting (Review)

Steady-state ablation of aluminium alloys by a CO2laser

“…Aluminium alloys are more difficult to cut or weld with a CO2 laser than are most other structural metals, mainly because aluminium has a relatively low absorptance (i.e. low 'couplingcoefficient', orhigh reflectivity) atthelaserwavelengthof 10.6 ,pm (Touloukian and De Witt 1970, Babenko and Tychinskii 1973, Cunningham and Laughlin 1974, Ready 1978. These alloys also appear to respond inconsistently to laser radiation because their absorptances, which vary with time during heating and melting, are very sensitive to surface finish and surface oxidation (Touloukian andDe Witt 1970, Babenko andTychinskii 1973).…”

The influence of gas jet velocity in laser heating—a moving workpiece case

“…The laser heating of surfaces, in general, is a gasassisted process; in this case, the function of the assisting gas is either to protect the surface against an oxidizing environment or to cool down the surface for improved hardness [12]. When modelling the laser heating process, therefore, the eect of the assisting gas should be considered, i.e.…”

An experimental and theoretical study of heat transfer effects during a laser-cutting process

“…Several review articles have also appeared in the literature that have detailed the state-of-the-art research in the laser cutting of metals. An early review of the field was done by Babenko and Tychinskii [7] which looked at work in the Soviet Union and elsewhere. They also presented a physical model of the cutting process which resulted in a set of nomograms which gave the cutting velocity and power for any material.…”

“…7 shows a photograph of the detector head assembly consisting of the high temperature range lens-tube covered with the protective sheath, the fiber-optic light source connecting to the back of the detector head, the calibration light source, the low-temperature range lens-tube, and the demodulating and amplifying board.…”