How do lasers cut metal

What is a laser cutter

A Laser cutter is a computer numerically controlled machine that is used to cut or engrave material by directing a focused high power laser beam to the material. Lasers are known to be one of the most viable and efficient methods of cutting metal plates. They can be used to cut mild steel, aluminum plates, and stainless steel to produce complex shapes. They are preferred for metal cutting because the computer controls allow for quick cutting with high precision. In addition, the lasers also have high cutting tolerances and they never make direct contact with the metals. This enables them to produce small-sized holes even when cutting thick metal plates, learn more at

How they work

So how do lasers cut metal? Lasers work by focusing a laser beam through a laser cutting head using a reflecting mirror or some special lens. The beam which is a high intensity light of one color and wavelength is focused onto a point on the metal. The density of the beam should also be consistent and round to ensure a quality cut. When the beam is focused on one point, the heat density on that point becomes intense. This high concentration of heat on point is important for cutting thicker metals since the more the heat the better it cuts thicker metals.

The focused high energy beam will burn the metal and melt it at that point and even partially or completely vaporize it. All one is required to do is to move the laser cutting head along the cutting line on the metal sheet to give the desired shape.
There is a sensory height control unit that helps in maintaining a distance between the head of the laser and the metal sheet being cut. This distance is essential as it helps the one cutting to determine the size and density of the focal point. The smaller the distance between the end of the nozzle and the workpiece the smaller the focal point and vice versa. This, therefore, means lowering and raising the focal point determines the quality of the cut as it reduces the possibility of warping. Some other factors that determine cut quality are accuracy in cutting as well as a stable laser. Focusing the beam accurately will help in reducing the kerf and produce a fine edge that does not require finishing.

Types of lasers.

There are two main types of lasers used to cut metal. They are essentially made similar but with varying power range. Each can, therefore, be used in cutting metal sheets with different thickness and material. The main lasers used include; CO2 Lasers and Neodymium lasers.

CO2 Lasers.

In these lasers, the laser beam is formed from an electrically stimulated mixture of gases comprising of mostly carbon dioxide. These lasers can be used to cut and shape bulky steel plates of thickness up to 25 millimeters.

Neodymium lasers.

These lasers use a laser beam from neodymium-doped crystals. They can be used to trim thin gauge steel and to cut sheet metals