Laser-cutting,Using Light to Shape Matter.SOLUTIONS with Effective, Practical AdviceLaser-cutting or, more correctly, Laser Beam Cutting, is an application of laser technology that enables shaping of a great variety of materials including metals of all kinds, from inexpensive steels to special alloys, but also plastics, paper, wood, leather, rubber and more. As a process it is enjoying exceptional and rapid expansion to many industrial manufacturing activities due to its unique advantages in economy, productivity, part precision and quality, material utilization and production flexibility. (Sponsored Links) Furthermore, as no contact is made while cutting, the process leaves no marks or contamination of the material. High quality cuts are obtained with no extra finishing operations. The Laser is essentially a beam of monochromatic coherent light. A lens concentrates it into a very small spot of highly intensified energy, capable of vaporizing most materials either with or without the use of an additional gas, coaxial with the laser beam, to blow away drops of molten material (nitrogen) or to burn them (oxygen), leaving sometimes a blackened edge. The parameters that determine the applicability of the process to different materials and that establish the cutting quality are light wavelength, power, beam quality and spot size. Pulsed lasers are used for precise cutting of thin metals and continuous wave (CW) are used for Laser-cutting widely ranging material thickness. A pulsed laser outputs short time powerful bursts of energy, useful for piercing the material to start a cut in the interior of a sheet or plate. Typically, the diameter of a focused process laser beam is about 0.20 mm, concentrating 1000 to 4000 watts of energy at the focal spot. This is enough to melt or vaporize most common materials. Aluminum and copper are highly reflective materials. To improve their ability to be cut by laser they should be covered with a light absorbing layer colored black. In the past gas lasers based on Carbon Dioxide (CO2) were used exclusively for elevated powers, which was achieved with limited efficiency. Newer solid state (crystal) lasers compete now with them even at relatively high power levels. The optical fiber lasers with computer controlled pulses facilitate Laser-cutting of intricate features in thin material like cardiovascular stents and silicon wafers for solar panels. The pulsed mode results in minimal recast layer and Heat Affected Zone, very critical to special applications. The widely varying depth of field and the small spot sizes produce small kerfs and straight walls even in thick metals. High power multimode lasers permit Laser-cutting of automotive body parts, of holes for riveting in alloys of aluminum and titanium for aerospace applications, and of thick plates for the shipbuilding industry. Laser-cutting machines are integrated into large computer controlled systems that implements design files on workpieces. Laser-cutting machines move either the cutting head or the metal or both. For maximum speed and efficiency, high performance precision systems, using ball screws and linear motors, move the low inertia parts including optical fibers and cutting head, while heavy materials are kept stationary on pallets. In Laser-cutting, the minimum radius for internal corners is about 0.75 mm (0.030 in). The minimum hole size can be as low as 20% of the stock thickness, depending on thickness. Nesting parts to be cut within the given surface and cutting along common lines, as well as stacking sheets, allow considerable economies to be realized. Job shops can provide the advantages of this processing to interested parties. A short note on Laser-cutting appears in our page onwww.welding-advisers.com/Cutting-torch.html Almost eighty references to the Laser subject as treated in our website and in the periodic publications Practical Welding Letter, can be found by running a Google search in any of our website pages. More than seventy articles on Laser-cutting can be found at Any questions or comments or feedback? Write them down and send them to us by e-mail. Click on the Contact Us button in the NavBar at top left of every page.
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