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:17 Iss:1 (Microstructural characterization of dissimilar laser weld between austenitic and ferritic stainless steels)

Authors:
Rakesh Kaul
P. Ganesh
A. K. Nath
Industrial CO2 Laser Section, Centre for Advanced Technology, P. O. CAT, Indore 452 013, India

The present work involved microstructural characterization of thin sheet dissimilar laser welds between type 304 austenitic stainless steel and stabilized 17% Cr ferritic stainless steel and their comparison with welds produced by autogenous gas tungsten arc welding (GTAW). Low heat input of laser welding (LW) effectively reduced the size of fusion zone (FZ) and heat affected zone (HAZ). LW with focused laser beam (LB), preferentially displaced towards austenitic stainless steel (ASS), produced FZ with uniform and highly ref...

JLA Vol:21 Iss:3 (Infrared observations and finite element modeling of a laser transmission welding process)

Authors:
L. S. Mayboudi
A. M. Birk
G. Zak
Mechanical and Materials Engineering, Queen’s University, Kingston, Ontario K7L 3N6, Canada

P. J. Bates
Chemistry and Chemical Engineering, Royal Military College, Kingston, Ontario K7K 7B4, Canada

Laser transmission welding (LTW), a technique to join thermoplastic components, involves a laser beam passing through a laser-transmitting part and then being absorbed by the laser-absorbing part at the weld interface. To form a strong bond, it is important that the weld interface be exposed to sufficient heat to melt the polymer without degrading it. A lap-joint geometry was investigated and the...

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:25 Iss:4 (On the exposure limits for extended source multiple pulse laser exposures)

JLA Vol:15 Iss:2 (Plasma assisted laser surface alloying)

Authors:
M. H. McCay
C. M. Sharp
J. A. Hopkins
The Center for Laser Applications, The University of Tennessee Space Institute, Tullahoma, Tennessee 37388

B. Szapiro
The Department of Physics, University of the South, Sewanee, Tennessee

T. D. McCay
The Center for Laser Applications, The University of Tennessee Space Institute, Tullahoma, Tennessee 37388

The combination of plasma arc with a Nd:YAG laser during surface alloying produces a synergistic effect which significantly increases the depth of the melt pool beyond that expected by a summation of the individual depths. Incremental increases in laser power produce ...

JLA Vol:19 Iss:3 (Femtosecond pulsed laser microfabrication of SiC MEMS microgripper)

Authors:
Monica Vendan
Pal Molian
Mechanical Engineering Department, Iowa State University, Ames, Iowa 50011

We report the capability of an ultrafast laser to pattern an electrostatic-comb-drive microgripper in the chemically difficult-to-etch 3C-SiC thin films. A microgripper with overall dimensions 1.2 mm×0.35 mm and a gap of 20 μm was designed and fabricated for the purpose of grasping and transporting microscale objects in hostile and harsh environments. Atmospheric pressure chemical vapor deposition was used to deposit thin films (∼2 μm) of 3C-SiC on 〈100〉 silicon substrates. A Ti:sapphire laser with 120 fs pulse wid...

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,...