JLA Vol:21 Iss:3 (Laser welding of galvanized DP980 steel assisted by the GTAW preheating in a gap-free lap joint configuration)
Center for Advanced Manufacturing, Southern Methodist University, Dallas, Texas, USA 75205
With the increasing need for reducing the vehicle’s weight, improving fuel efficiency and safety, as well as the corrosion resistance, more and more galvanized high-strength steels have been used in the automotive industry. However, the successful laser welding of galvanized steels in gap-free lap joint configuration is still a big challenge. The high-pressurized zinc vapor is readily developed at the interface of the two metal sheets due to the lower boiling point of zinc (around 906 °C) than the melting point of steel (over 13...
JLA Vol:8 Iss:2 (Recent progress in laser surface treatment: <emph type="4">II</emph>. Adopted processing for high efficiency and quality)
Institut fu¨r Strahlwerkzeuge, Universita¨t Stuttgart, Pfaffenwaldring 43, 70569 Stuttgart, Germany
Iof this contribution, energy coupling and transport mechanisms were considered in detail. The second part concentrates on the effect of the spatial distribution of the energy in the laser beam, which will be discussed in connection with applications of laser surface technologies. Along these lines, a variety of beam shaping facilities is presented for laser hardening and cladding. Their purpose is to adapt the irradiated area to the workpiece ge...
Jae H. Lee
Institut fu¨r Strahlwerkzeuge, University of Stuttgart, Federal Republic of Germany
In cutting or welding processes with lasers, deep penetration mechanisms allow high energy coupling rates. In surface treatment processes such as martensitic hardening, cladding and alloying, deep penetration of the laser beam is mostly not applicable. This generally leads to insufficient coupling rates. In this contribution several ways of enhancing the coupling rate are summarized. Following some theoretical considerations, results of exp...
JLA Vol:15 Iss:3 (Three-dimensional finite element modeling of laser cladding by powder injection: Effects of powder feedrate and travel speed on the process)
University of Waterloo, Department of Mechanical Engineering, Waterloo, Ontario N2L 3G1, Canada
This article addresses a novel three-dimensional transient finite element model of the laser cladding by powder injection process. The proposed model can predict clad geometry as a function of time and process parameters including beam velocity, laser power, powder jet geometry, laser pulse shaping, and material properties. In the proposed method, the interaction between powder and melt pool are assumed to be decoupled and as a result, the melt pool boundary is first obtained in the absence of powder spray....
JLA Vol:19 Iss:3 (Characteristics of the laser clad metal made with powder mixture of Co-based alloy and vanadium carbide)
Graduate School of Engineering, Nagoya University, 1 Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
A powder mixture of Co-based alloy (Stellite-6) and vanadium carbide (VC) was deposited to substrates of SM400B mild steel and SUS304 stainless steel using a 2.4 kW cw CO2 laser. The mechanism of crack for clad metal was investigated by changing the VC weight fraction in the range of 0%–56%. The microstructures of the clad layer for matrix of Co-based alloy can be classified into two types—hypoeutectic structure (0–12 wt % VC) and hypereutectic structure (13–56&ens...
JLA Vol:24 Iss:3 (Investigation of the effects of basic laser material interaction parameters in laser welding)
W. J. Suder
S. W. Williams
Welding Engineering and Laser Processing Centre, Cranfield University, MK43 0AL, United Kingdom
The depth of penetration achieved in continuous wave (CW) laser welding results from a balance of many complicated phenomena, which are linked with the characteristics of the heat source. In this work, the laser welding process has been investigated in terms of basic laser material interaction parameters: power density and interaction time. It has been shown that these two parameters are insufficient to characterize the laser welding process. Thus, a third parameter, specific point energy, has been introduced, which along with the power densi...
North Salinas High School Salinas, CA 93906, U.S.A.
Laser light is an instant attention‐getter in the classroom; thus any activity which uses the laser as an instructional tool is sure to enhance student motivation. This paper discusses two demonstrations and one experiment involving laser applications that the author has found to be particularly beneficial in terms of (1) instructional effectiveness and (2) arousing the interest of high school physics students. Brief descriptions follow. Refraction through lenses can be nicely illustrated by splitting laser light into several parallel beams and directing them through a fish tank filled with a scatt...
JLA Vol:18 Iss:1 (Cladding of Stellite-6 and vanadium carbide on carbon steel using a yttrium–aluminum–garnet laser robot system)
Graduate School of Engineering, Nagoya University, 1 Furo-cho Chikusa-ku, Nagoya 464-8603, Japan
School of Engineering, Nagoya University, 1 Furo-cho Chikusa-ku, Nagoya 464-8603, Japan
In the present work, a laser robot system was setup for cladding and repairing machinery parts using pulsed 300 W Nd:yttrium–aluminum–garnet laser facility, six-axis robot, optical fiber, powder feeding system with a special nozzle for powder supply. A mild steel plate was deposited with powder mixtures of Stellite-6 alloy and vanadium carbide (VC). The shape of clad layer, microstructure, and its wear perfo...
Richard J. Coyle
Patrick P. Solan
AT&T Bell Laboratories Engineering Research Center, Princeton, NJ 08542‐0900, U.S.A.
The majority of industrial lasers used in manufacturing are Class
IVlasers. Engineering and administrative control measures appropriate to that class of lasers must be enforced to ensure their safe use in production environments, i.e. they should be designed into Class 1 laser systems. In addition, several other design characteristics unique to industrial applications are normally incorporated into these Class Isystems, such as interlocked enclosures, process mon...
There is currently no content classified with this term.