However,
for some applications – such as housings for control cabinets or components of
high-voltage batteries for electric vehicles – a V-0 classification in the UL
94 flammability test from the US testing institute Underwriters Laboratories
Inc. is often mandatory.
For
such cases, Lanxess has developed three new halogen-free, flame-retardant Tepex
variants with a polyamide 6 matrix. “These structural materials are the
material of choice when a V-0 classification is required and the components
need to have a very high degree of strength, rigidity and energy absorption at
the same time,” explains Sabrina Anders, Project Manager at the Lanxess subsidiary
Bond-Laminates in Brilon, Germany, where Tepex is developed and produced.
Three product variants available
Tepex
dynalite 102fr-RG600(x)/47% is reinforced with roving glass fibers. These can
also be arranged multiaxially and thus precisely matched to the load transfer
points and load paths in the component. The composite is universally applicable
and is suitable for high-voltage components of electric vehicle batteries, such
as separator plates, cover plates and control unit housings. In contrast, Tepex
dynalite 102fr-FG290 is targeted at applications in the electrical and
electronics sector. With its reinforcement of fine glass fiber, it produces
high-quality surfaces that are easy to paint. It is suitable, for example, for
small housings that are required to comply with the DIN EN 45545-2 standard,
“Railway applications – Fire protection on railway vehicles”. Tepex dynalite
202fr is reinforced with carbon fibers and is intended for components subjected
to extreme mechanical stress, such as high-strength electronic housings.
According to Anders, “It is an alternative to composites made of
flame-retardant polycarbonate if their strength and rigidity are not
sufficient, for example.”
Mechanical
properties match those of standard products
All
three structural materials are available in quantities for large-scale
applications. They are also available in variants that are electromagnetically
shielded by a carbon textile insert in the composite or a metallic surface
coating. The UL 94 V-0 classification refers to specimen thicknesses of between
0.5 and 3.5 millimeters. “The flame-retardant additives are selected so that
the mechanical properties of the composites are not negatively affected and are
comparable to those of corresponding standard materials. For example, the
flexural strength of Tepex dynalite 202fr is well over 600 megapascal,”
explains Simon Rösen, materials developer at Bond-Laminates. All
flame-retardant packages comply with the EU RoHS (Restriction of Hazardous
Substances) Directive and the European REACH regulation (Registration,
Evaluation and Authorisation and Restriction of Chemicals, Regulation (EC) No
1907/2006)).