EuroWire March 2016

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March 2016 70
Last year was an exciting time for the
Plasmait team. The company sold a range
of plasma heat and surface treatment
machines in the ferrous and non-ferrous
markets.
Plasma is proving its performance in an
increasingly wide range of materials, from
mainstream copper alloy and aluminium
wire to specialist medical tubes and
ropes, jewellery strands, aerospace
materials, electronics and semi-conductor
wire and strip.
Most significant is Plasmait’s success in
the stainless steel and nickel alloy wire
and tube markets. Deployments included
annealing lines for large and intermediate
stainless steel wire boasting a single
line output of 150kg/h and more for
martensitic stainless steels.
Stainless steel wires from 1 to 10mm
can now be produced scratch-free and
pile-free at high speed. Superior surface
and homogeneous recrystallisation with
small grain improves subsequent drawing
and reduces the number of wire breaks
on the drawing machine.
The new fine wire annealing line allows
recrystallisation annealing at up to 25m/s
on a range of fine stainless steel and
nickel alloy wires. It is now possible to
anneal fine stainless wires in-line with the
drawing machine. Annealing fine wire at
up to 20 times the speed of a traditional
strand furnace means fewer take-ups and
pay-offs and hence lower cost of total
capital investment.
The PlasmaAnnealer can cold start
production in a few minutes and be
stopped immediately. This avoids long
heating-up and cooling-down times
and associated energy costs that are
symptomatic of a conventional tube
furnace.
The first plasma annealer for taped
copper conductors has been in operation
for more than a decade. The latest one
was installed in 2015. The shortcomings
of the traditionally used batch annealing
process can be avoided with continuous
plasma annealing and if cleaning is used
in front of the taping line.
Round or rectangular conductors can
be plasma annealed and cleaned in-line
with a conventional taping line. Plasma
annealed conductors feature better
accuracy in mechanical properties and
better surface finish, which results in
superior tape adhesion.
Plasma heat and surface treatment
can be effectively deployed for plating
applications.
Plasma-treated copper or aluminium
wires can be hot-dip coated or
electroplated without the need for
chemical cleaning or fluxing. For example,
PV ribbon can be annealed to a super-soft
state and tinned without the need for
chemicals.
Plasma surface activation can also
improve lubricant pickup in a drawing
line. Plasma surface treatment ensures
good lubricant adhesion during the
drawing of stainless steel or titanium rods.
Surface activation is achieved at low
temperatures, which makes the process
particularly economical compared to
expensive-to-run traditional processes
such as brushing, acid treatment or sand
blasting.
Among the latest deployments was a
plasma annealer for stranded conductors
and ropes. The annealer was designed
to allow for rapid heat penetration
through the cross-section of the stranded
construction. With plasma heat treatment,
the individual wires can be annealed or
stress relieved to equal temper/softness.
Plasmait GmbH – Austria
Website:
Versatile heat and surface treatment
▲ ▲ Plasma is proving its performance in an increasingly wide range of materials