Rami Arieli: "The
Laser Adventure" Section 9.1.3 page 1
9.1.3 Material working
The main advantages of lasers
for material processing are:
-
Very high accuracy in the final processed
products that can be obtained without the need for polishing.
-
No wearing of mechanical tools. Mechanical
tools change their dimensions during the working process, and require constant
measurements and feedback to adapt their position to original plan in computerized
instrumentation.
Material processing include many kinds of processes.
A partial list include:
-
Cutting - The
laser can be a very precise cutting tool. High power lasers are used for
cutting steel, while other lasers are used to cut fabrics, rubber, plastic,
or any other material.
-
Welding - Combining
(fusing) two materials together. By heating the materials near the connecting
region, the materials melt locally, and fuse together.
-
Hardening - By
heating specific areas of the material, most metals can be hardened most
of the metals. Even local hardening
of specific part of a tool can be done by local irradiation.
-
Melting - Absorption
of laser beams caused a rise in temperature. Since very high power can
be transferred to materials in a very short time, melting can be easily
done.
-
Evaporating -
Used to ablate material (transfer it into the gas phase).
-
Photolithography -
specially in the semiconductor industry. Very delicate shapes can be created
in materials which are used for masks in photolithography. Special materials
respond to light at specific wavelength by changing their properties. Thus
it is possible to remove parts of the material with very high precision
(in micrometer range).
-
3-D Laser measurements
- With the help of a scanning laser, it is possible to obtain the
information about a shape of a three-dimensional object and put it in the
computer.
-
3-D Stereo lithography -
Similar to photolithography, but the laser is used to create three dimensional
sculpture of the information stored within a computer.
A combination of the last two applications enable creating
3-D models. Even statue of people were build with high accuracy
using these techniques.