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Laser Machining of Metals
Published in V. K. Jain, Advanced Machining Science, 2023
Cutting is one of the first applications of lasers in manufacturing. Laser cutting is a widely used process in the industry due to its simplicity and accuracy. It is generally used for cutting sheet metals. Laser cutting can be performed using both CW lasers and pulsed lasers. Laser cutting involves focusing the laser beam to narrow sizes on the workpiece to heat and remove the material through melting or vaporization. Cutting is achieved by moving the laser with a certain scanning speed along the workpiece by producing a slot, also called a kerf. It can be used for both straight and contour cutting. Laser cutting has several advantages. The process is not only fast but can also be used to cut intricate shapes, which are otherwise difficult to cut using conventional techniques. The kerf width in laser cutting is very narrow, and hence the material loss is minimal [3]. Based on the material removal mechanisms involved, laser cutting may be categorized into two different types – fusion cutting and sublimation cutting.
Solid Materials: Joining Processes
Published in Leo Alting, Geoffrey Boothroyd, Manufacturing Engineering Processes, 2020
Laser beam welding is a metal joining process that produces melting of materials with the heat obtained from a narrow beam of coherent, monochromatic light. This beam can travel long distances without attenuation and may be focused through lenses to produce spots in which the energy density amounts to over 1012 W/m2 and is equaled only by the electron beam. No vacuum chamber is required for the generation and delivery of the beam, which is generated in a laser medium (gas: CO2; solids: Nd-YAG), each type having specific characteristics. The laser output can be pulsed or continuous. Shielding gas blown through a nozzle most often coaxially with the beam protects the weld. Typically, no filler material is used.
Radiation—ionising and non-ionising
Published in Sue Reed, Dino Pisaniello, Geza Benke, Kerrie Burton, Principles of Occupational Health & Hygiene, 2020
Lasers have a wide range of industrial and commercial applications, including as alignment and range-finding in construction, printing, drilling, welding, cutting, advertising and entertainment. Lasers are also used for surgery and ophthalmic procedures, and as pointers in lectures and business presentations.
Towards sustainable production for transition to additive manufacturing: a case study in the manufacturing industry
Published in International Journal of Production Research, 2023
Neslihan Top, Ismail Sahin, Sachin Kumar Mangla, Muruvvet Deniz Sezer, Yigit Kazancoglu
Laser engraving is the etching of the surface of an object with a laser beam. Laser engravers for processing wood, metal, plastic, leather and glass surfaces can be of different sizes and functions. Besides, these machines are advantageous due to their light and portable features. Within the scope of the study, a commercial Desktop LEM produced by conventional methods was examined. The case of the device is 21 × 21 × 23 cm and consists of eight parts. These parts are the plates (six parts) forming the body of the machine and mounting bases (two parts) to which the electronic equipment is attached. Apart from these, fasteners (screws), electronic equipment, motors and the table are components that make up a typical LEM. The LEM body is made of aluminium with mounting bases made of stainless steel.
Stress waves in laser-material interaction: From atomistic understanding to nanoscale characterization
Published in Journal of Thermal Stresses, 2023
To date, lasers have been widely used in material processing, synthesis, and manufacturing. Examples include pulsed laser deposition, laser shock peening, laser welding, 3D additive manufacturing, and 3D subtractive manufacturing [1–5]. The involved pulsed laser-material interaction spans time domains of ms, μs, down to fs time scale. Under intense laser irradiation, the target material will experience extremely fast heating, melting, vaporization, and phase explosion with an extremely high-temperature gradient in the material. This very large temperature gradient will form extremely high-stress waves that can propagate in the material, and whose existence will cause strong structure alteration, destruction, and affect the subsequent solidification and crystallization processes. Because of the intensive physical processes, experimental, theoretical, and numerical modeling studies of laser-material interaction and the stress waves become very challenging. Despite extensive work reported in the past, tremendous research is still being conducted worldwide in this area. This article is not intended to provide an extensive review of stress waves in laser-material interaction, which is truly a broad topic. Rather we focus on the research we have conducted that covers theoretical work, numerical modeling (mostly molecular dynamics [MD] simulation), and experimental characterization of stress waves during laser-material interaction, and elaborate on our perspectives in this area.
An investigation of surface quality characteristics of 3D printed PLA plates cut by CO2 laser using experimental design
Published in Materials and Manufacturing Processes, 2021
J.D. Kechagias, K. Ninikas, M. Petousis, N. Vidakis, N. Vaxevanidis
Laser cutting (LC) is a non-conventional material removal process that cuts the material locally by melting it with thermal energy by a laser beam.[1] During the motion of the laser beam upon the cutting surface, a kerf (or taper geometry) is formed.[2] A variety of materials, such as metals, plastics, ceramics and composites, are cut by lasers in various industrial applications due to the flexibility of the process.[3,4] Laser cutting together with other Laser Material Processes (LMP) methods (laser engraving, laser machining, etc.) are applied extensively to manufacturing sectors such as vehicles and airplanes fabrication.[5,6] The post-processing of the items produced either by traditional or modern (non-conventional) methods is critical for improving the quality of the final product.[7]