When it comes to cutting sheet metal, laser cutting is the preferred processing method for producing precision machined parts because it creates more precise and smoother lines than mechanical cutting. The process of laser cutting flat sheet material uses a machine that sends a laser beam through the material that cuts using heat. Once the subject of science fiction stories, laser machining is becoming more and more prevalent in industrial applications as laser cutting machines are becoming more affordable.
Even though sheet metal laser cutting machines are becoming more accessible, they still use significant amounts of electrical power to produce lasers hot enough to melt sheet metals such as steel. Laser cutting machines can use from 1,000 watts to over 8,000 watts of power to produce a laser. Laser beams used in industrial laser cutting can range in thickness. Usually, the thinner the laser, the more heat it can produce, so very thin lasers are generally used for sheet metal laser cutting.
Most industrial laser cutting machines come in three types: moving material, flying optics, and the hybrid configuration. The moving material configuration is popular in sheet metal laser cutting because the flat sheet material moves while the laser stays stationary at a fixed distance from the sheet metal. Flying optics laser cutting machines work the opposite way, with a moving laser and fixed sheet metal. The hybrid configuration for sheet metal laser cutting machines lets both the sheet metal and the laser move.
Several different types of lasers can be used for sheet metal laser cutting and engraving. Lasers used in cutting sheet metal like steel or aluminum are the same kinds of lasers also used in welding, called carbon dioxide (CO2) lasers, neodymium (Nd) lasers, or neodymium yttrium-aluminum-garnet (Nd-YAG) lasers. Usually, Nd and Nd-YAG lasers are used for boring and engraving, while CO2 lasers are more commonly used for cutting sheet metal and other materials.
In sheet metal laser cutting, there are several factors which affect the type of laser that is used in different applications. The type of metal can greatly affect the thickness and intensity of the laser beam used because certain metals like aluminum can conduct heat away from the laser, making laser cutting less efficient. For thicker sheet metal, laser cutting machines sometimes use a method called reactive cutting to efficiently cut hard or thick metal. Pulsing lasers can also cut precise holes in sheet metal.