Wobble Mode
Circle
(CW & CCW)
Linear
Eight
Infnity
Schematic Sample Weld
Welding Seam
Wobble
Welding Seam
Wobble
Welding Seam
Wobble
Welding Seam
Wobble
12 Industrial Laser Solutions MARCH/APRIL 2017 www.industrial-lasers.com
METHOD WORKS WITH SINGLE-MODE
AND MULTIMODE FIBER LASERS
BRYCE SAMSON, TONY HOULT, and MUSTAFA COSKUN
The move towards adopting lighter and stronger materi- als in everyday products, from automobiles to consumer electronics, has led to a number of significant challenges in welding these structures, especially in high-volume production environments. Examples in the transporta- tion industry include electric vehicle infrastructure, where battery manufacturing often requires joining of dissimilar highly reflective materials such as aluminum and copper.
Further adoption of high-strength steels, together with aluminum and magnesium composites for weight reduction in automobiles, is another related example.
In consumer electronics, the requirements for lightweight structures with highly
tailored thermal and electrical properties are constantly driving the need for more
complex designs, often using thin foils and requiring joining of dissimilar metals,
again with aluminum and copper being the heavily featured materials. The medical device industry is also driving the need for joining small metal parts, often with
dissimilar materials.
Growth of laser welding has been ongoing for over a decade, with the automotive industry—an early adopter of the technology—being the first to see the benefits of an automated joining process combined with the intrinsic advantages of fiber
laser technology. However, the challenges of laser welding many of the materials
described previously have remained significant and could explain the slow rate of
the adoption of laser welding in some applications.
Recently, the introduc-
tion of a new, cost-effective,
easy-to-integrate technol-
ogy, based on a beam wob-
bling technique, is helping
to overcome some of these
difficulties in welding mate-
rials such as copper and
aluminum with high-bright-
ness fiber lasers at 1µm.
This technique is helping to
overcome porosity and hot
cracking issues with laser
welding of some materi-
als, while helping to make
part fit-up 3X more forgiv-
ing in some of the examples
technology report
FIGURE 1. Examples of wobble shapes from commercially
available welding wobble heads, with independent adjustable
amplitude and frequency control up to 300Hz.
FIGURE 2. Examples of 6061-T6 aluminum
welds using the beam-wobble technique.
discussed in this article. By enabling independent control of penetration depth, spot
velocity, weld speed, and seam width, the
technique has applications in welding
small, temperature-sensitive assemblies
(for medical parts)—poorly fitted parts that
can be difficult to laser-weld and cosmetically attractive to weld without the need for
post-processing.
Wobble head technology
FIGURE 1 demonstrates the con-
cept of the 2D dynamic beam
motion or wobble head technology, where the four basic
programmable shapes avail-
able from an industry-standard
welding head, such as the D30
from IPG Photonics, are shown.
Independent control of the
amplitude and frequency of the
oscillation is achieved through
the galvo-mirror controller,
allowing more flexibility in stabilizing the keyhole melt during
the welding process, with typical
frequencies up to 300Hz used in
