JLA Vol:20 Iss:2 (Laser bioeffects associated with ultrafast lasers: Role of multiphoton absorption)

Authors:
Randolph D. Glickman
Department of Ophthalmology, University of Texas Health Science Center, San Antonio, Texas 78229-3900

Thomas E. Johnson
Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, Colorado 80523

Gary D. Noojin
David J. Stolarski
Michael L. Denton
Northrup Grumman Warfighter and Applications Department, San Antonio, Texas 78228-1330

Neeru Kumar
Department of Ophthalmology, University of Texas Health Science Center, San Antonio, Texas 78229-3900

Benjamin A. Rockwell
US Air Force Research Laboratory, AFRL/HEDO, Brooks City...

JLA Vol:25 Iss:4 (Passive and active protective clothing against laser radiation)

JLA Vol:9 Iss:6 (Effect of nozzle orientation on the gas dynamics of inert-gas laser cutting of mild steel)

Authors:
Aaron D. Brandt
Gary S. Settles
Gas Dynamics Laboratory, Mechanical Engineering Department, Penn State University, University Park, PA 16802, U.S.A.

This investigation applies sonic and supersonic coaxial and off‐axis nozzles to the cutting of mild steel sheet of 1–4 mm thickness. A 1.5 kW CW CO₂ laser is used with nitrogen as the assist gas. Sonic coaxial cutting is compared to that of off‐axis nozzles, which vary in orientation from 20–60° behind the laser axis and in exit Mach number from 1 to 2.4. Results show a 50% increase in maximum cutting speed at approximately a 40° off‐axis nozzle angle. In com...

JLA Vol:3 Iss:3 (Treating Birthmarks With Diabetes)

Authors:
Myron L. Wolbarsht
Psychology Department, Duke University

JLA Vol:16 Iss:4 (Laser transmission welding of polymer and wood composites: Material and joint mechanism related studies)

Authors:
H. Haferkamp
A. von Busse
S. Barcikowski
A. Ostendorf
J. Bunte
Laser Zentrum Hannover e.V., Hollerithallee 8, 30419 Hannover, Germany

Laser beam transmission welding is an innovative and promising technology for many industries such as the automotive, electronic, and medical industry. Extension to application of this technology to wood components makes it also interesting for the woodworking and furniture industry. Therefore, several investigations in the field of welding of fiber reinforced thermoplastic and wood composites with polymers have been carried out. Focus is given to the determination of the weldability and weld ...

JLA Vol:21 Iss:1 (Visualization of events inside kerfs during laser cutting of fusible metal)

Authors:
Peter Yudin
Oleg Kovalev
Khristianovich Institute of Theoretical and Applied Mechanics, Novosibirsk, 630090, Russia

The subject of the research is mechanism of melt removal and striated roughness generation. Being the main obstacle limiting laser cutting process performance, these phenomena are widely discussed. Available theoretical descriptions are not conclusive, as they have nothing to be verified with. High temperatures and narrowness of the kerf severely limit visual access at a real facility. Observation will become possible if one wall of the kerf is made of glass. This possibility is utilized in present experiments, which reproduce the process at low tem...

JLA Vol:26 Iss:1 (Investigation on reducing distortion by preheating during manufacture of aluminum components using selective laser melting)

Authors:
Damien Buchbinder
Wilhelm Meiners
Norbert Pirch
Konrad Wissenbach
Fraunhofer Institute for Laser Technology (ILT), Aachen 52074, Germany

Johannes Schrage
Chair for Laser Technology, RWTH Aachen University, Germany 52024, Aachen

The additive manufacturing process selective laser melting (SLM) can be used to directly produce functional components made out of metal. During the construction process, however, thermally induced residual stress occurs due to the layered build-up and the local input of energy by means of a focused laser beam, which can lead to distortion of the component or sections of the component itself....

JLA Vol:24 Iss:2 (Synthesis of nitrogen-doped diamond films using vibrational excitation of ammonia molecules in laser-assisted combustion flames)

Authors:
L. S. Fan
Z. Q. Xie
J. B. Park
X. N. He
Y. S. Zhou
Department of Electrical Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0511

L. Jiang
Department of Mechanical and Automation Engineering, Beijing Institute of Technology, Beijing 100081, People’s Republic of China

Y. F. Lu
Department of Electrical Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0511

Nitrogen-doped diamond was synthesized in open air using laser-assisted combustion flame method. A wavelength-tunable CO₂ laser was used to resonantly excite the vibration mod...

JLA Vol:6 Iss:3 (Acoustic emission response of soda lime glass after a single Nd‐YAG laser pulse)

Authors:
R. Harrysson
P. Vomacka
Department of Engineering Materials, Luleå University of Technology, S‐951 87 Luleå, Sweden

When machining brittle solids with a laser, crack formation can occur in the material around the irradiated area causing a strength reduction of the machined material. The purpose of this work was to study a well known brittle material (soda lime glass) by means of acoustic emission (AE) in order to investigate the correlation between visually observed crack formation and detected AE energy released by the crack formation in the material. During and after irradiation of soda lime glass with an Nd‐YAG laser pulse, the number...

JLA Vol:15 Iss:1 (Dual laser beam modification of high alumina ceramics)

Authors:
D. Triantafyllidis
Array

J. R. Bernstein
Corrosion and Protection Centre, University of Manchester Institute of Science and Technology, Manchester M60 1QD, United Kingdom

L. Li
Department of Mechanical, Aerospace and Manufacturing Engineering, University of Manchester Institute of Science and Technology, Manchester M60 1QD, United Kingdom

F. H. Stott
Corrosion and Protection Centre, University of Manchester Institute of Science and Technology, Manchester M60 1QD, United Kingdom

Alumina-based refractory materials are extensively used in high-temperature applications, such as linings in waste incinerators. A sign...