Laser Cutting
Solid state JK Nd:YAG Lasers and JK Fiber Lasers lasers can be used to cut metals, some ceramics and plastics, and graphite composites. eCO2 lasers address thin metal, paper, wood, plastic, fabrics, and 
other non-metal cutting applications. Laser Glass Cutting Can also be carried out in the same way.
The key benefits of laser cutting include:
- Applicability to a wide range of materials and thickness
- Narrow kerf widths
- High speeds
- Very high repeatability
- Very high reliability
- Easily automated and programmable
- Flexibility in changeovers
- Reduced tooling costs and reduced setup times
- Non-contact process (no tooling wear or breakage, minimal material distortion)
- Versatility (the same tool can also be used for laser drilling and laser welding)
- Capacity for high degree of beam manipulation (true 3-D cutting)
The Laser Cutting Process
Cutting requires that the laser beam is focused by a lens to a small focus spot, typically in the 25-100µm diameter range for fine cutting and 100um to 300µm range for thicker section cutting. Coaxial gas is delivered just above laser focus by a nozzle that surrounds the converging laser beam to keep the optics clean and improve the cutting process by pushing the vaporised and liquefied material out through the kerf. Gases such as oxygen and air are used to promote cutting of ferrous alloys and cellulose materials. Air is often used with plastics and fabrics. High-pressure inert gas is used when cutting some metals to leave an un-oxidized edge with little dross.
When to select a Fiber Laser
The fiber lasers beam quality allows very fine cutting with kerf widths of less than 20um in thin section metals of <200um thickness being possible. With such a fine kerf, cut speeds of 10's m/min are possible in a range of metals, ceramics and also semiconductor materials such as silicon. With the possibility of modulating the beam at high frequency and fast response times very high speed cutting of small features is possible with very high accuracy and repeatability.
When to select a Pulsed Nd:YAG laser
Pulsed YAG lasers are used for medium to heavy section cutting. The higher-powered pulsed JK Lasers have kerf widths down to about 100µm and cut thicknesses of over 25mm are possible. Pulsed YAG lasers can perform very high tolerance cutting because of their high peak power and low average power which efficiently vaporises a lot of the material and keeps the total heat input low. Cutting tolerances in material of less than 1mm can be better than 10µm and in thicker materials the tolerance is in the 25µm range.
When you should consider a Continuous Wave (CW) Nd:YAG laser
CW and Super Modulated JK Lasers can cut with kerf widths in the 250-300µm range and cut at high speeds in metals up to 10mm. Cutting with these lower peak power lasers depends upon the laser’s average power for speed. Since these lasers are not limited by pulse to pulse overlap during cutting they can cut thinner materials at a higher rate. Additionally, some of these laser models have a patent-pending Super Modulation feature which can significantly improve cutting speed and in zinc-coated steels, aluminum alloys or when cutting at an angle to the surface
Benefits of using Fiber Delivery on your Nd:YAG laser
For fine cutting with a kerf in the 20-80µm range most tasks require beam delivery with mirrors from the laser to the lens. For kerf widths in the 80-400µm range fiber optic delivery can be employed. Special fiber optic delivery focus heads incorporate coaxial gas nozzles and even auto-focus control for cutting surfaces with varying height or when robotic manipulation is used.
Let us help you select the right laser for your cutting process
GSI Group has Applications Centers around the world to help you develop a laser cutting solution for you. We can provide minimum support such as determining the appropriate laser source, beam delivery, and cutting parameters. For other projects we can help with fixture development, custom optical systems, controls integration, and the production of test articles.
Laser cutting is a well-established process, and has gained wide acceptance in manufacturing due to the many advantages and benefits that the laser can provide over other cutting methods.
We now have a designated page on Laser Glass Cutting with further information if you are looking for resources on glass cutting!
You can also find our White Paper on Zero Width Cutting with Co2 Laser for further reading.