E/M Coating Services
www.emcoatingsuk.co.uk
COMPANY PROFILE
At the forefront of the latest designs,
materials and technologies, E/M Coating
Services pride themselves on offering high
quality coating applications and processes
to improve performance and extend the
life of critical components and fabrications
of all shapes and sizes for a wide range of
industrial sectors. With specialised facilities
we are able to design and manufacture
bespoke coating systems and have
in-house NACE Level 3 trained Inspectors.
Quality is at the heart of our business
and we operate under the highest quality
control procedures including AS9100 Rev
C, NADCAP, ISO9001/9008 and NACE.
New Anti-Corrosion Coating for
Rare Earth Magnets
Neodymium Iron Boron magnets
are utilised in a wide number of
industries, including the highly
demanding wind turbine industry.
A multitude of these magnets are bonded
together to increase the overall level of
magnetism. This process leads to two
potential issues: Firstly, any adhesive or
coating between the magnets acts as an air
gap and thus reduces the level of
magnetism and secondly NdFeB magnets
corrode extremely aggressively. This
corrosion issue is exacerbated by the
environmental conditions that the wind
turbines face.
The corrosion mechanism for NdFeB
magnets is detailed in Figure 1. This shows
that when exposed to water or humid
conditions, the Neodymium rich layers at
the grain boundaries react to form
Neodymium Hydroxide. The effect of this
conversion from Nd to Nd(OH)3, is a large
volume increase along the grain boundaries,
leading to cracking and degradation of
magnet properties.
Curtiss-Wright Surface Technologies
(CWST) has been working on a solution to
these issues. This involved developing a
high grade anti-corrosion coating with
minimal coat thickness (effective air gap).
The current market leader for corrosion
protection is CWST’s own Everlube 6155
providing 500 hours protection in the ASTM
B117 salt spray test.
After extensive studies and trials, CWST is
pleased to announce they have successfully
developed a coating system which will
provide 1,000 hours salt spray resistance
for NdFeB magnets at a coating thickness
of just 25um. This NEW coating system –
Everlube 1155 is environmentally friendly,
easy to apply and a cost effective solution to
this critical problem. Please call on
+44 (0)1386 421444 for further
details.
Nd rich phase
Exposure to humidity
or salt spray
Nd2Fe14B
E/M Coating Services are a business unit
of Surface Technologies, a Division of
Curtiss-Wright, who are global specialists
in surface treatments to improve the life
and performance of critical components
and preventing premature failures
through their network of over 75 facilities
worldwide. www.cwst.co.uk
Figure 1: Shows the corrosion mechanism for NdFeB rare earth magnets.
Nd(OH) 3
Exposure to humidity
or salt spray
E/M Coating Services
Curtiss-Wright, Enterprise Way, Vale Industrial Park, Evesham, Worcestershire WR11 1GX, UK
l Tel: +44 (0)1386 421444
For more information on all our services and full worldwide contact details: www.cwst.co.uk