This document discusses laser applications in surface modifications. It begins by defining lasers and how they work, producing a coherent beam of light through stimulated emission. The document outlines different types of lasers and their general applications. It then focuses on laser surface modification techniques, which can induce physical and chemical changes to surfaces. Specific applications of laser surface modification are discussed, such as increasing hardness, strength, and fatigue life while reducing friction and wear. The document concludes by stating lasers have unique properties making them useful for precision surface heating treatments in engineering applications.

1. Laser Applications in Surface
Modifications
By K.Prem Kumar
13R05A0311

2. CONTENT
 LASER DEFINITION
HOW LASER WORKS
TYPES OF LASER’S
GENERAL APPLICATIONS OF LASER
LASER SURFACE MODIFICATIONS
APPLICATIONS OF LASERS IN SURFACE ENGG
AND SURFACE MODIFICATIONS

3. LASER
Light Amplification by Stimulated Emission of
Radiation

4. DEFINITION OF LASER
DEFINITION: A laser is a device which is built
on the principles of quantum mechanics to
create a beam of light where all of the
photons are in a coherent state - usually with
the same frequency and phase.

5. Emission of a laser beam

6. WORKING OF LASER
In simplest terms, a laser uses light to stimulate
the electrons in a "gain medium" into an excited
state (called optical pumping). When the
electrons collapse into the lower-energy
unexcited state, they emit photons . These
photons pass between two mirrors, so there are
more and more photons exciting the gain
medium, "amplifying" the intensity of the beam.
A narrow hole in one of the mirrors allows a small
amount of the light to escape (i.e. the laser beam
itself).

7. Ordinary and laser light sources

8. TYPES OF LASERS
SOLID STATE LASERS
LIQUID(DYE) LASERS
GAS LASERS
SEMI CONDUCTOR LASERS
CHEMICAL LASERS
X-RAY LASERS

9. General applications of lasers

10. Laser surface modification process
Laser Surface modification (LSM) covers a
wide spectrum of surface modification routes.
This can induce physical changes like changes
in surface morphology and roughness, as well
as chemical changes like changes in chemical
composition.

11. Laser surface modification (LSM)
The laser has some unique properties for surface
heating
The electromagnetic radiation of a laser beam is
absorbed within the top atomic layers for opaque
materials, such as metals
There are no associated hot gas jets, eddy
currents or even radiation spillage outside the
optically defined beam area
 In fact the applied energy can be placed precisely
on the surface only where it is needed

12. Laser surface Applications
Hardness increase
Strength increase
Reduced friction
Wear reduction
Increase in fatigue life
Surface carbide creation
Creation of unique geometrical wear patterns
Tempering

13. Applications of lasers in surface
engineering

14. Applications of lasers in surface
modifications

16. Typical laser applications

17. By K.Prem Kumar(stunner)
13R05A0311