JLA Vol:4 Iss:3 (Laser Safety Primer Outline for Industrial/Medical Users)

Authors:
T. J. Glynn
M. Walsh
National Centre for Laser Applications, Physics Dept., University College, Galway, Ireland

Laser safety standards are detailed technical documents arising from the complexity of the different mechanisms, depending on the parameters of the laser beam, by which lasers interact with living tissue. As a result, their interpretation by non‐expert laser users, who are concerned about safety issues, can cause many difficulties. Based on experience in advising industrial and medical laser users, we have developed a primer which (i) provides step‐by‐step guidance in the interpretation and use of the laser saf...

JLA Vol:14 Iss:2 (Thermomechanical effects in laser microprocessing for dieless metal wire drawing)

Authors:
Yonggang Li
School of Optic/CREOL (Center for Research and Education of Optics and Lasers), Mechanical, Materials and Aerospace Engineering Department, University of Central Florida, Orlando, Florida, 32816-2700

Nathaniel R. Quick
USF Filtration and Separations Group, Inc., 1750 Filter Drive, DeLand, Florida 32724-2045

Aravinda Kar
School of Optic/CREOL (Center for Research and Education of Optics and Lasers), Mechanical, Materials and Aerospace Engineering Department, University of Central Florida, Orlando, Florida, 32816-2700

A new dieless metal fiber drawing process is developed in which a high-precision laser is used to heat the...

JLA Vol:18 Iss:3 (Thermal and microstructural aspects of the laser direct metal deposition of waspaloy)

Authors:
Andrew J. Pinkerton
Laser Processing Research Centre, School of Mechanical, Aerospace and Civil Engineering, The University of Manchester, PO Box 88, Manchester M60 1QD, United Kingdom

Mallikarjun Karadge
Manchester Materials Science Centre, School of Materials, The University of Manchester, Grosvenor Street, Manchester M1 7HS, United Kingdom

Waheed Ul Haq Syed
Lin Li
Laser Processing Research Centre, School of Mechanical, Aerospace and Civil Engineering, The University of Manchester, PO Box 88, Manchester M60 1QD, United Kingdom

A potential problem in applying the laser direct metal deposition (LDMD) technique to the f...

JLA Vol:23 Iss:2 (Recent advances in laser surface treatment of titanium alloys)

Authors:
J. J. Candel
V. Amigo´
ITM Instituto de Tecnologia de Materiales, UPV, Valencia, Spain

This paper reviews progress over the last five years in the field of laser surface modification of titanium alloys. The authors analyze the effect of new laser technologies and new materials as tools for improving surface properties—specifically, biocompatibility and resistance to wear, corrosion, and high temperatures. The authors discuss the effect of laser processing parameters on the microstructure and compare the results obtained by various researchers. Therefore, an overview of the difficulties involved in the laser processing of titanium is provided with a di...

JLA Vol:7 Iss:4 (Laser cutting of thick sectioned steels using gas flow impingement on the erosion front)

Authors:
P. M. Ilavarasan
P. A. Molian
Department of Mechanical Engineering, Iowa State University, Ames, IA 50011, U.S.A.

An off‐axial gas jet has been developed that has the potential to extend the laser's effectiveness by improving the rate at which parts can be machined, producing high‐quality surfaces, enhancing the cutting thickness, and adding to the range of materials that can be machined. In laser cutting, an erosion front (liquid–gas region) forms at the momentary end of the cut. Laser heating, exothermic reactions and shear force between the gas flow and the molten layer dictate the material removal rates. The principle of the off‐axi...

JLA Vol:26 Iss:1 (Periodic antireflection surface structure fabricated on silicon by four-beam laser interference lithography)

Authors:
Z. Zhang
CNM and JR3CN, Changchun University of Science and Technology, Changchun 130022, China and CHO, Changchun Observatory, National Astronomical Observatory, CAS, Changchun 130117, China

Z. Wang
D. Wang
CNM and JR3CN, Changchun University of Science and Technology, Changchun 130022, China and JR3CN, University of Bedfordshire, Luton LU1 3JU, United Kingdom

Y. Ding
CNM and JR3CN, Changchun University of Science and Technology, Changchun 130022, China

Silicon surface structures with excellent antireflection property arouse wide interest. Chemical and physical methods such as femtosecond, nanosecond, and picosecond la...

JLA Vol:16 Iss:4 (Dimensional and material characteristics of direct deposited H13 tool steel by CO₂ laser)

Authors:
J. Choi
Y. Hua
Department of Mechanical and Aerospace Engineering and Engineering Mechanics, University of Missouri, Rolla, Missouri 65409-1060

Laser aided direct metal/material deposition process builds metal parts layer-by-layer directly from the computer aided design representation. Success of this technology in the die and tool industry depends on the parts quality to be achieved. To get designed geometric dimensions and material properties, delicate control of the process variables such as laser power, spot diameter, traverse speed, and powder mass flow rate is critical. With a closed loop optical height control system, the dimensional accuracy was achieved ...

JLA Vol:21 Iss:2 (Corrosion performance and restoration of laser-formed metallic alloy sheets)

Authors:
Z. Liu
C. Guzma´n
H. Liu
A. Anacleto
T. Francisco
M. Abdoalshafie
L. Ma
O. Abodunrin
P. Skeldon

Previous studies of laser forming have been focused on understanding the laser forming mechanisms, investigating the effects of important laser process parameters on deformed shape, and modeling the forming process. Although microstructures and mechanical properties have received some attention, no work has addressed corrosion behavior of laser-formed components. However, laser forming is a thermal process with substantial thermal cycles required; sensitization of microstr...

JLA Vol:9 Iss:6 (… .But is it really safe?)

Authors:
Peter A. Smith
DERA Centre for Human Sciences, Farnborough, Hampshire, U.K.

JLA Vol:3 Iss:2 (Laser Applications in Criminalistics)

Authors:
E. R. Menzel
Center for Forensic Studies, Department of Physics, Texas Tech University, Lubbock, Texas 79409

Lasers find application in numerous areas of criminalistics, such as fiber analysis, document examination and serology. Their widest use, however, is in detection of latent fingerprints. Several routine procedures for obtaining laser‐excited fingerprint fluorescence on a range of surfaces have been developed. However, many surfaces fluoresce so strongly themselves that they are not amenable to these procedures. Time‐resolved luminescence imaging is being investigated to permit detection of fingerprints on such surfaces.