Laser Cutting: How It Works

Laser cutting is a technique that uses a beam of high intensity light of a single wavelength to cut materials.  This high-powered beam of light is controlled by computerized numerical parameters using G-code.  The positioning accuracy of laser cutters is 10 micrometers with repeat-ability of 5 micrometers.  This leaves a high-quality surface edge that is very accurate.

There are two types of laser cutting formats, gantry and galvanometer systems.  In the gantry system the laser is positioned perpendicular to the material and plots the beam over the surface.  The galvanometer system uses mirrors, or “beam benders”, to bounce the laser beam into the proper position. The galvanometer is a much faster system than the gantry format which allows fabricators to increase production levels.

There are three main forms of lasers used in laser cutting.

CO2: This form of laser is suited for boring, cutting, and engraving.

Neodymium (Nd): Used in boring where high energy and low repetition is involved.

Neodymium yttrium aluminum garnet (Nd:YAG): Used in welding, boring, and engraving where very high power is required.

Laser cutting uses numerous methods to cut different types of material.  The four main methods are thermal stress cracking, vaporization, melt and blow and flame cutting.

Thermal Stress Cracking: This method is used mostly in brittle materials that are conducive to thermal fracture.  A crack is formed and guided by the laser beam using localized heat and thermal expansion.

Vaporization Cutting: The laser beam heats up an area on the material to boiling point which produces a keyhole.  The vapor deepens the hole and the molten wall further expands the hole.  Wood and plastics are cut by this method.

Melt And Blow: Also known as  fusion cutting, heats the material to melting point and then uses high-pressure gas to blow the molten material from the cutting area.  This method reduces the power required to cut the material which is usually metal.

Flame Cutting: Also called “reactive cutting”, “burning stabilized laser gas cutting”.  Flame cutting is a lot like oxygen torch cutting using a laser as the ignition.  This process is used to cut thick steel material with very little laser power needed.

Conclusion: As you can see, laser cutting is a very popular and time efficient way of cutting a variety of materials.   Laser cutting is already a stable and reliable way of cutting and with the advent of new technology in the future, the sky’s the limit as to how fast and accurate new laser cutters will be.