للكاتب :
A.M. KOHAIL
Mech Eng., Prod. Dept.(R), MTC , Cairo
ABSTRACT
Laser drilling has been widely used in industry. The laser drilling process occurs when the
laser beam is focused with enough intensity to melt and vaporize the drilled substrate. The
high throughput energy rate is one of the most important laser drilling advantages. Most of
laser material processing techniques use a gas jet in tandom with laser beam to accelerate
metal removal rate and it helps also for ejection of molten metal from cutting zone.In this
study three different types of assist gases were used for drilling of 1 mm thick stainless steel
substrate using Nd:Yag pulsed laser head with maximum power of 400 W. The used gases are
Oxygen,Nitrogen and Argon with a pressure varying from 2 to 6 bar. The laser beam was
delivered at different pulse energy and pulse shape. Scanning electron microscope was used
to capture the images of the drilled holes with spatter deposition area. Optical tool maker
microscope was used to measure both inlet and exit hole diameters to evaluate taper. The
obtained results showed the considerable influence of both assist gas type and pressure on
drilled holes geometrical configurations and accuracy at different pulse energy.