LASER BEAM MACHININGSAHIL DEV (10406EN016)

MECH IDD PART V

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Contents

Laser Beam Machining

Laser

Type of Laser

Laser Application

Parameters Affecting LBM

Advantage

Disadvantage

References

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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

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Elements of Laser

Lasing Medium (Gas, liquid, solid)

Pumping process

Optical feedback element

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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

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Source: Google Images

Effect of Laser Beam on Material 6

Source: Internet

Types

of Laser

Gas Laser

Solid State

Laser

Excimer

Laser

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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

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He-Ne Gas Laser 9

Source: Google Images

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

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Ruby Laser 11

Source: HowStuffWorks

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’

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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.

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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

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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

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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

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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

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Parameter Affecting LBM• Working Material

• Assist Gases

• Focusing Lenses

• Laser Beam

• Environment

Laser Beam

Machining

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Advantages

Non Contact

No solvent chemical

Selective material removal

Flexibility

Fully automated

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Disadvantages

Requires specially trained operators

Not for mass metal removal processes

Requires greater control of joint tolerances

Expensive equipment

Consumes much energy

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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

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THANK YOU

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