The application of YAG-SLAB lasers operating in fundamental and low order mode
to metal cutting has been investigated. The high beam quality and the relative
insensitivity of the beam shape to average power variations make slab lasers
strong candidates for high precision cutting applications. The advantage of very
fine focusability (focused beam diameters down to 30,um) and high intensity
(100 MW/cm2) for cutting applications are shown. Three limiting factors are
derived for high quality cutting : The threshold intensity for efficient laser
beam absorption, the depth of focus of the laser beam and the limited aspect
ratio (cutting thickness to kerf width ratio) achievable by material removal.
Experimental results of stainless steel cutting with fundamental and low order
mode beams are given for material thicknesses of 0.5 mm to 1.5 mm. The cuts show
kerf widths of 35im (aspect ratios of 21:1) and roughness values of Ra 1.6 pm
for 0.8 mm thick steel samples.