JLA Vol:9 Iss:2 (Laser cladding with a pulsed Nd:YAG laser and optical fibers)

Authors:
M. Brandt
D. A. Scott
S. B. Emms
J. M. Yellup

A new laser cladding technique for producing wear and corrosion resistant surfaces on engineering components is reported. The technique involves the combination of the pre‐placed and injected powder delivery methods for producing clad layers. The clad layers were formed with a pulsed Nd:YAG laser and optical fibers. The results using a nickel‐based alloy (Hastelloy C) indicate that uniform clad layers in excess of 1 mm in thickness can be achieved in a single pass with 240 W average power incident on the workpiece. The laser beam was delivered through a step‐index glass ...

JLA Vol:4 Iss:3 (High Tech or High Risk — The laser on your manufacturing floor)

Authors:
Tom Wiley
Lumonics Industrial Products Division

JLA Vol:16 Iss:1 (Laser-induced electrochemical characteristics of aluminum alloy 2024-T3)

Authors:
Olga Kachurina
Tammy L. Metroke
Kai Dou
Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078

Laser-induced surface modification of aluminum alloy 2024-T3 was investigated as laser intensity dependence of surface composition and patterning related to electrochemical characteristics using techniques of environmental scanning electron microscopy (ESEM), potentiodynamic scan, and electrochemical impedance spectroscopy (EIS). Analysis of surface composition using ESEM and EIS indicated that laser fluences in a range of 1.1–1.3 J/cm² were found to preferentially reduce the copper concentration in the alloy surf...

JLA Vol:20 Iss:2 (Review of exposure limits and experimental data for corneal and lenticular damage from short pulsed UV and IR laser radiation)

Authors:
Karl Schulmeister
Austrian Research Centers, A-2444 Seibersdorf, Austria

David H. Sliney
US Army Center for Health Promotion and Preventive Medicine, Aberdeen Proving Ground, Maryland 21010-5422

John Mellerio
Department of Ophthalmology, Rayne Institute, St. Thomas’ Hospital, London, SE1 7EH, United Kingdom

David J. Lund
Bruce E. Stuck
US Army Medical Research Detachment, Walter Reed Army Institute of Research, Brooks City-Base, San Antonio, Texas 78235-5108

Joseph A. Zuclich
Northrop Grumman Information Technology, San Antonio, Texas 78288-1330

Laser exposure limits as ...

JLA Vol:23 Iss:2 (Microcomputed tomography analysis of intralayer porosity generation in laser direct metal deposition and its causes)

Authors:
M. Naveed Ahsan
Laser Processing Research Centre, School of Mechanical, Aerospace and Civil Engineering, University of Manchester, Sackville Street, Manchester M13 9PL, United Kingdom

Robert Bradley
Henry Moseley X-ray Imaging Facility, School of Materials, University of Manchester, Grosvenor Street, Manchester M13 9PL, United Kingdom

Andrew J. Pinkerton
Laser Processing Research Centre, School of Mechanical, Aerospace and Civil Engineering, University of Manchester, Sackville Street, Manchester M13 9PL, United Kingdom

Laser direct metal deposition has wide application in the areas of rapid manufacturing, surface coating, and compon...

JLA Vol:7 Iss:4 (Laser applications in science education (LASE) Project: an introduction to photonics at the secondary school level)

Authors:
Gareth T. Williams
Physics Department, San Jose State University, San Jose, California, U.S.A.

JLA Vol:14 Iss:3 (Appropriate regimes of laser drilling models containing melt eject mechanisms)

Authors:
S. S. Kudesia
Department of Physics, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, United Kingdom

P. Solana
Departamento de Matema´tica Aplicada, Universidad Polite´cnica de Madrid, Spain

W. S. O. Rodden
D. P. Hand
J. D. C. Jones
Department of Physics, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, United Kingdom

The significance of melt ejection during various drilling regimes of laser drilling is investigated. The predictions of two analytical models of the drilling process, with and without the melt ejection mechanism, are compared with experimental measurements made using a ...

JLA Vol:18 Iss:3 (Multiscale modeling of solidification during laser cladding process)

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

Laser cladding is an additive manufacturing process in which a laser generates a melt pool on the substrate material while a second material in a powder or wire form is injected into that melt pool. Among all laser manufacturing processes, laser cladding offers the most extensive variety of possibilities to alter a component at its surface. Despite immense potential and advancements, the process model of microstructure evolution and its coupling with macro parameters of the laser cladding process has not been fully developed. To address this...

JLA Vol:8 Iss:1 (Laser polarimeters: Overview of recent developments, design and applications)

Authors:
Vi´ctor Fajer Avila
Center for the Development of Scientific Equipment and Instruments, Ministry of Science Techonology and Environment, Havana, Cuba

Research carried out in Cuba has led to the design and construction of automatic polarimeters that use the He‐Ne laser as a luminous source and work on a magnetooptic principle of measurement. Physical and chemical investigations including the use of the He‐Ne laser as a light source are discussed. The principle of measurement for the design and construction of polarimeters, resulting in three different types of these instruments, is described. Finally, applications for magnetooptic polarimetry are described,...

JLA Vol:3 Iss:1 (Laser Welding Copper and Copper Alloys)

Authors:
Kaoru Hashimoto
Takehiko Sato
Koichi Niwa
Fujitsu Laboratories Ltd., 10‐1, Morinosato‐Wakamiya, Atsugi 243‐01, Japan

We have developed a laser hermetic sealing technique that combines nickel plating with laser welding for copper and copper alloy bellows for general purpose large‐scale computers. Laser welding of copper has been difficult because of copper's high thermal conductivity and reflectivity. However, laser welding nickel‐plated copper results in deep penetration. To avoid corrosion induced at the dissimilar metal contact between nickel and copper, the nickel‐plated copper was heat‐treated bef...