![]() Lasers are ideal for cutting metal as they provide clean cuts with a smooth finish. The laser is amplified in a glass fibre to produce a far smaller spot size than that achieved with CO 2 techniques, making it ideal for cutting reflective metals.Ĭutting metal is one of the most common applications of laser cutting and is used on materials including stainless and mild steel, tungsten, nickel, brass and aluminium. This technology uses a solid gain medium rather than a liquid or gas. The water also offers the advantage of removing debris and cooling the material, while other advantages over ‘dry’ laser cutting include high dicing speeds, parallel kerf, and omnidirectional cutting.įibre lasers are also gaining popularity in the metal cutting industry. One example of water cooled laser processing is a laser microjet system, which couples a pulsed laser beam with a low-pressure water jet to guide the beam in the same manner as an optical fibre. Water is a frequently used coolant, often circulated through a heat transfer or chiller system. Waste heat can be transferred directly to the air, but a coolant is commonly used. Transverse flow lasers use a simple blower to circulate the gas mix at a lower velocity, while slab or diffusion resonators use a static gas field which requires no pressurisation or glassware.ĭifferent techniques are also used to cool the laser generator and external optics, depending on the system size and configuration. Fast axial flow uses a mixture of carbon dioxide, helium and nitrogen circulated at a high velocity by a turbine or blower. Common variants of CO 2 laser include fast axial flow, slow axial flow, transverse flow, and slab. The RF method has external electrodes and thereby avoids problems related to electrode erosion and plating of the electrode material on glassware and optics that can occur with DC, which uses an electrode inside the cavity.Īnother factor that can affect laser performance is the type of gas flow. This process can be broken down into three main techniques - CO 2 laser (for cutting, boring, and engraving), and neodymium (Nd) and neodymium yttrium-aluminium-garnet (Nd:YAG), which are identical in style, with Nd being used for high energy, low repetition boring and Nd:YAG used for very high-power boring and engraving.Īll types of lasers can be used for welding.ĬO 2 lasers involve the passing of a current through a gas mix (DC-excited) or, more popularly these days, using the newer technique of radio frequency energy (RF-excited). ![]() Where the laser cutting process needs to start anywhere other than the edge of the material, a piercing process is used, whereby a high power pulsed laser makes a hole in the material, for example taking 5-15 seconds to burn through a 0.5-inch-thick (13 mm) stainless steel sheet. This light is focused at the work area by mirrors or fibre optics that direct the beam through a lens which intensifies it.Īt its narrowest point, a laser beam is typically under 0.0125 inches (0.32 mm) in diameter, but kerf widths as small as 0.004 inches (0.10mm) are possible depending on material thickness. The lasing material is amplified by being reflected internally via a partial mirror until its energy is enough for it to escape as a stream of coherent monochromatic light. The laser beam is created by the stimulation of lasing materials through electrical discharges or lamps inside a closed container. The focused laser beam burns, melts, vaporises or is blown away by a jet of gas to leave a high-quality surface finished edge. Typically, the process uses a motion control system to follow a CNC or G-code of the pattern that is to be cut onto the material. Laser cutting uses a high-power laser which is directed through optics and computer numerical control (CNC) to direct the beam or material. Click here to see our latest technical engineering podcasts on YouTube. This article is one of a series of TWI frequently asked questions (FAQs). ![]() Laser cutting is a process that uses a laser to cut different materials for both industrial and more artistic applications, such as etching. National Structural Integrity Research Centre.Structural Integrity Research Foundation.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |