Date post: | 13-Jul-2015 |
Category: |
Engineering |
Upload: | sahil-dev |
View: | 2,616 times |
Download: | 10 times |
Contents
Laser Beam Machining
Laser
Type of Laser
Laser Application
Parameters Affecting LBM
Advantage
Disadvantage
References
2
What is Laser
LASER is the acronym for Light Amplified Stimulated Emission of Radiation
Laser is a device which generates or amplifies light
Stimulated emission of electromagnetic radiation
Coherent, monochromatic, directional and high power laser beam is used
3
Laser Beam Machining
Used light energy from a laser to remove material by vaporization and ablation
Energy is concentrated optically
Laser emits either continuous or pulsed light beam
5
Source: Google Images
Gas Laser
Electric current is discharged through a gas to produce a coherent light
Operate on the principle of converting electric energy into laser light output
Gas acts as pumping medium to attain the necessary population inversion
Common gas laser are CO2 Gas Laser, He-Ne Gas Laser
8
Solid State Laser
Constructed by doping a rare earth element into a variety of host materials
Pumped optically by arc lamps or flash lamps
Respond well to Q-switching
Ruby or Nd:YAG is the most common host material
10
Excimer Laser
Uses a combination of an inert gas and reactive gas
Excimer is form of Ultraviolet Chemical Laser
Excimer is short for ‘excited dimer’
12
Source: Google Images
Dye & Semiconductor Laser
Dye Laser
use complex organic dyes, such as rhodamine 6G
Semiconductor Laser
sometimes called diode lasers
very small and use low power.
13
Operation: Laser Cutting
Cutting starts by drilling a hole by moving beam
Cutting speed depends on material and thickness
Both pulsed and continuous laser is used
Thickness ranges from 0.5-1 inch
Used for cutting complex geometry and for clean cutting operation
14
Source: sciencedirect.com
Laser Welding
For welding ceramics and dissimilar materials like steel and aluminum
Produces maximum penetration and minimum distortion in materials
Beam can be easily shaped, focused and directed
Application
Razor Blade
Electronic Circuit
15
Laser Cladding
Used to improve surface quality by applying a corrosion resistant layer on product
Laser Beam is used to create a shallow melt pool
Metal powder is supply using an inert gas flow
Application
Chemical industry
Mining and marine application
16
Source: Wikipedia
Laser Application
Heavy
Manufacturing
Seam & spot
welding
Cladding &
drilling
Light
Manufacturing
Engraving
Drilling
Electronics
Skiving of
circuits
Wire stripping
Medical
Cosmetic
Surgery
Hair removal
17
Parameter Affecting LBM• Working Material
• Assist Gases
• Focusing Lenses
• Laser Beam
• Environment
Laser Beam
Machining
18
Advantages
Non Contact
No solvent chemical
Selective material removal
Flexibility
Fully automated
19
Disadvantages
Requires specially trained operators
Not for mass metal removal processes
Requires greater control of joint tolerances
Expensive equipment
Consumes much energy
20
References
http://www.google.com
http://www.sciencedirect.com
http://en.wikipedia.org/wiki/laser_cutting
http://www.gobookee.org/powerpoint-of-laser-beam-machining/
Laser beam machining (LBM), state of the art and new opportunities/Johan Meijer
http://science.howstuffworks.com/laser.htm
21