This paper contains CO2 laser cutting results in mild and stainless steel with different laser sources. The main factors which affect the cutting speed and quality are the power, the cutting gas and focal point conditions. Keeping the power and cutting gas constant, the focal point conditions have been varied with respect to size and power density.In the introduction a theoretical model is presented, showing that the cutting speed is inverse proportional to the width of the cut kerf in a given material, and the definition of the Beam Quality Factor is introduced.In the next chapter this theory is proven at least for oxyfuel cutting of mild steel, whereas fusion cutting of stainless steel is more complicated.Cutting results from 7 different indus-trial laser sources connected to different moving systems, were used to get information about the importance of the Beam Quality Number K and focal spot size,for the maximum cutting speed. One of the 7 laser sources with different focal length and thus different minimum spot size, was then used to investigate more in details the importance of the focal spot size cutting stainless steel with high pressure nitrogen. It looks as if there is a strong connection between the smallest avail-able spot size and cutting speed in mild steel, whereas the conditions in stainless steel, depends strongly on the flow conditions in the cut kerf, and not only on the focal spot size.
|Journal||Welding in the World|
|Publication status||Published - 1996|