Laser drilling works by using a concentrated laser beam to melt or vaporize material. It can drill small diameter holes with high depth-to-diameter ratios much faster than conventional drilling. The laser characteristics can be adjusted to suit different materials. Laser drilling is used in applications like aircraft turbine engines and printed circuit boards due to its precision and ability to drill complex hole geometries at high speeds. It allows for flexible, automated production with advantages like non-contact processing and multi-material compatibility. However, laser drilling cannot precisely control blind hole depth and is slower for larger holes.

1. Gateway Institute Of Engg. &
Technology
Topic – LASER DRILLING
Submitted To:-
Mr. Nikhil Rohilla
A.P. In M.E. Deptt.
Submitted By:-
Deepak Kumar
14010004012
4th
year
B.Tech (Mech.)

3. •The Laser (light amplification by stimulated
emission of radiation) devices are those which
convert one form of energy into photons which are
electromagnetic radiations.
•Laser drilling works on the principle of transferring
light energy from the surface through fibre optic
cabling – which transmits light with little or no loss of
energy through Total Internal Reflection – to a
series of lenses which direct the laser light to the
surface of the rock.
LASER

4. •This concentrated beam of light is capable of
cutting rock many times faster than the
conventional method of drilling.
•Laser is a device which generates or amplifies
light
• Stimulated emission of electromagnetic
radiation
• Coherent, monochromatic, directional and high
power laser beam is used

5. Elements of Laser
•Lasing Medium (Gas, liquid, solid)
•Pumping process
•Optical feedback element

6. •Laser drilling of cylindrical holes generally occurs
through melting and vaporization (also referred to as
"ablation") of the workpiece material through absorption of
energy from a focused laser beam.
•The energy required to remove material by melting is about
25% of that needed to vaporize the same volume, so a
process that removes material by melting is often favored.
•In laser drilling, sufficient heat must be applied to raise the
local temperatures so that they exceed the melting point of the
rock. Once that threshold value is exceeded, the amount of
energy required to remove a piece of rock remains almost
constant.

7. •
•The diameter of these holes can be as small as
0.002”.
• If larger holes are required, the laser is moved
around the circumference of the “popped” hole until
the desired diameter is created; this technique is
called “trepanning”.
•The laser characteristics can be adjusted from the
surface depending on the lithological characteristics
•Whether melting or vaporization is more dominant in
a laser drilling process depends on many factors,
with laser pulse duration and energy playing an
important role.

8. •To quantify the amount of energy needed, a
parameter called specific energy (SE) is used. SE is
defined as the amount of energy required removing a
unit volume of rock and is given by:
SE= (Energy Input) /(Volume of Rock removed)=
P/(dV ⁄dt)
Where,
P = Power Input (Watts)
dV/dt = Volume Time Derivative (cm3/sec)
Its is expressed in kW/ (cm³⁄s) or kJ/cm³

10. Applications:-
•Laser drilling is one of the few techniques for producing high-
aspect-ratio holes—holes with a depth-to-diameter ratio much
greater than 10:1.
•Laser-drilled high-aspect-ratio holes are used in many
applications, including the oil gallery of some engine
blocks, aerospace turbine-engine cooling holes, laser
fusion components and printed circuit board micro-vias.
•Manufacture of turbine engines for aircraft
propulsion and for power generation
•Their ability to drill holes at shallow angles to the
surface at rates of between 0.3 and 3 holes per
second has enabled new designs incorporating film-
cooling holes for improved fuel efficiency, reduced
noise, and lower NOx and CO emissions.

11. Advantages:-
•Laser drilling is a non-contact process, meaning
that it causes little change to the materials it is
working with (except to drill holes of course!)
•Laser drilling offers precise control of beam
intensity, heat output, and duration, meaning it
consistently produces accurate results
•This level of control means that laser drilling can
drill shallow angles and different shaped holes
•Laser drilling can produce holes with small
diameters but high aspect ratio (this is where the
depth-to-diameter is greater than 10:1)

12. •Laser drilling is an automated process, and can
easily be programmed for different uses. It
allows for fast setup times and quick production
rates
•The same tool that is used for laser drilling can
also be used for laser welding and laser cutting,
making it an extremely versatile process
•Laser drilling can work with a number of
different materials
•Some laser drilling processes can drill multiple
features at the same time
•Laser drilling also offers flexibility when it
comes to changeovers for prototypes or small-
batch manufacturing

13. Disadvantages:-
•Cannot drill a blind hole to a precise depth.
•Laser technology to be supplied to field.
•Slower processing large holes