THE ANALYSIS OF CO2-LASER CUTTING

The laser finds increasing commercial use as a cutting tool. The laser cutting quality characteristics require microscopic evaluation of the resulting cut properties. Striation is considered as one of the impor tant quality characteristics and its formation is strongly related to cutting and workpiece parameters. However, the mechanism of formation of striations has not yet been well established. To enhance the unders tanding of striation and its properties, the present study is conducte d. A mathematical model relevant to formation of striation is develope d, and striation width and frequency are predicted. In the model a hea t transfer equation employing a moving heat source and allowing a chem ical reaction contribution to available power at the workpiece surface , due to an assisting gas effect, is introduced. The study is extended to include experimental investigation into the striation process. Con sequently, striation frequency and striation width are measured using the microphotography technique and a fibre-optic probe. It is found th at the mathematical model introduced represents the physical phenomena well, with the limits of characteristic distance, striation frequency and striation width, as predicted, agreeing well with the experimenta l findings.