REPAIR & REFURBISHMENT
bTwetote hr ethaadns o anree
TBy Steed Webzell
he metal additive
manufacturing (AM) process
has been integrated into
machine tools, ensuring they
are able to perform both
metal cutting and AM in sequential cycles.
Potential therefore exists to not only
create structures previously impossible to
make in metal, but repair high-value parts
back to original tolerances.
A case in point is the DMG Mori
Lasertec DED (directed energy
deposition) hybrid series, which e ectively
combines a ve-axis machining centre
or turning centre with AM capability that
delivers metal powder via a deposition
nozzle, essentially adding a bead of
weld to the part. Lasertec DED hybrid
machining centres, which o er both
ve-axis milling and ve-axis material
deposition, can process a wide range of
metal powders, including stainless steel,
tool steel and nickel alloys, while coating
materials include tungsten carbide and
Stellite.
“We can also manufacture parts from
a mix of materials, the applications for
which have started to increase over
the past 12-18 months,” explains Terry
Turner, business development manager -
additive manufacturing at DMG Mori UK.
“For instance, we have some customers
making speci c component features
in Inconel 718, to provide locationdependent
mechanical properties. Others
are producing automotive mould tools
with bronze in the core of the tool to pull
heat away from the surface, and tool steel
on the outside for wear resistance. This
Hybrid machining, comprising both
subtractive and additive processes, is
entering mainstream manufacturing
with the market now o ering several
state-of-the-art systems
results in a better cycle time for moulding
operations.”
DMG Mori is also seeing demand
for the repair of high-value parts and
aluminium die casting tools. “Rather
than using manual welding, we can
repair components with it in a far more
controlled way,” says Turner. “We can
monitor data and build exactly where
required, machine it back, build it up and
machine it back again to the required
geometry in one set-up.”
Although around 80 Lasertec DED
hybrid machines are now in use around
the world, there is only one in the UK, at
the University of She eld’s Advanced
Manufacturing Research Centre (AMRC).
Among the recent hybrid part production
projects at the AMRC was an aerospace
actuator component made from 15-5PH
stainless steel. The existing production
route for the part uses a solid bar
feedstock, but using hybrid manufacturing
it is possible to use tube. Hybrid trials
suggested that similar cycle times are
attainable, while reducing cost by 23% and
providing a large decrease in buy-to- y
ratio from 31:1 to 2.5:1.
PRECISION PARTS
Matsuura can argue that it is a true hybrid
pioneer, with an early version of its Lumex
model rst appearing in 2002. The Lumex
Avance of today uses DMLS (direct metal
laser sintering) as its AM technology,
making it suitable for high-precision parts
(example pictured above), particularly
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