Laser Cutting:
Laser cutting service is a process to cut different materials using laser technology. Laser cutting can also be defined as a technology which works by directing the output of a high-power laser most commonly through optics.
CNC Cutting:
CNC cutting is a computer-controlled cutting machine related to the router which are hand-held and used for cutting various materials which are hard to cut. It is also called as Computer Numerical Control cutting.
Both cutting methods are used to cut materials such as wood, composites, Aluminum, steel, plastics, foams, etc.
Process of generation of laser beam involves stimulating of a laser material by electric discharge from a closed container which has partial mirrors which reflects the beam from lasing material multiple times until it achieves sufficient energy to escape. The beam escape as monochromatic coherent light. This beam is focused and intensified by lenses or partial mirrors to a very small spot to create very intense beam of laser.
A normal laser is converted to a CNC cutting laser, when it is integrated with computer and operated through numerical inputs. It increases the efficiency of the laser and improve the quality of product. So, this is an Automated process which contrasts with machines that are manually controlled by hand wheels or levers. This automation has advantage over mechanical cutting as in includes easier work holding and reduced the contamination of workpiece which happens more during manual holding.
Types of Laser:
Following are the three types of Laser
- The CO2 Laser:
This type of laser cutting is pumped by passing current in the gas mixture or by using a radio frequency energy. CO2 Laser cutting is normally used for industrial cutting for materials like steel, paper, mild steel, stainless steel, plastics, wood,taskboard wax, fabrics, etc.
- The Neodymium (Nd) Laser:
Neodymium Laser cutting is used for boring and at the place where high energy but low repetition is required. Neodymium lasers are optically pumped using a flashtube or laser diodes.
- The Neodymium Yttrium-Aluminium-Garnet (Nd-YAG) Laser:
Neodymium Yttrium-Aluminium-Garnet (Nd-YAG) Laser cutting is like Neodymium Laser cutting. The only difference is Nd-YAG laser is used where very high power in needed for boring and engraving and ND where less repetition is required.
Methods of Laser Cutting:
Following are the different methods of Laser cutting:
- Vaporization Cutting:
In this type of cutting the focused beam heats the surface of the material to boiling point and generate keyhole. This keyhole leads to increase in absorptivity quickly deepening the hole. After the hole deepens and material boils and vapor generated erodes the molten walls.
- Melt and Blow:
In this type of cutting, it uses high-pressure gas to blow molten material from the cutting area. In the start, the material is heated to highest melting point and a gas jet blows the molten material out of the kerf. Materials cut with this process are usually metals.
- Thermal Stress Cracking:
In this type of cutting brittle materials are particularly sensitive to thermal fracture. A beam of light is focused at point which causes localized heating and thermal expansion of the material. This results in a crack in the material that can be guided by moving the beam.
- Stealth Dicing of Silicon Wafers:
In this type of cutting the separation of microelectronic chips in semiconductor device fabrication from silicon wafers may be performed by the so-called stealth dicing process.
- Reactive Cutting:
This type of cutting is like oxygen torch cutting but with a laser beam as the ignition source. Mainly used for cutting material like carbon steel in thicknesses over 1 mm. This types of process can be used to cut thick steel plates with relatively lesser laser power.
