JEC COMPOSITES MAGAZINE - Issue #121 - May 2018 - 62

TECHNOLOGY

62
67

Multi-material

High-confidence performance predictions for hybrid
thermoplastic composite applications
Experimental techniques

3D textile-reinforced composites: from manufacturing to
structural design

TECHNOLOGY multi-material

High-confidence performance predictions for
hybrid thermoplastic composite applications
SubhranSu Mohapatra,
Staff Scientist Data
Global Application Technology
Syed MuhaMMad KaShif,
Senior Scientist Composites
Warden Schijve,
Chief Scientist
Global Application Technology
recep yaldiz,
Staff Scientist, Composites
SABIC

Multi-material hybrid structures combining continuous fibre thermoplastic
composites with lower-cost options such as chopped fibre thermoplastic
composites and metals are an attractive proposition for many industries
due to their potential lower weight and cost. High confidence in performance
predictions is one of the key enablers to convert this potential into successful industry adoption. However, chopped and continuous fibre thermoplastic
composites pose numerous challenges for accurate predictions, due to the
inherent complexity of the material behaviour.
To establish confidence in predictions, a test component was designed that
can be produced in a representative production process and can validate all
of the many different composite failure modes.

C

ontinuous fibre-reinforced thermoplastic composite materials have been attracting industry attention for several years due to their high mechanical performance and
low weight. However, they are costlier than the current materials. Hence, multi-material hybrid structures that combine
continuous fibre composites with lower-cost options such
as chopped fibre composites and metals are becoming an attractive proposition for many industries due to the potential
simultaneous benefits of lower weight, higher mechanical performance and lower cost.
The advantage of this multi-material approach, when properly designed, is that it significantly reduces the percentage of
composite material, maximizing the use of the less expensive
overmoulding resin. Under this approach, high-performance
multiaxial UD tape-based laminates are used selectively along
the main load axis. At the same time, functional details can be
integrated using the injection moulding material, thus eliminating separate production steps. This way, the same high mechanical performance can still be achieved without the higher

62

jec composites magazine / N°121 May - June 2018

cost associated with these materials.However, these new materials require new robust manufacturing processes that must
comply with the industry standard short cycle times. New
predictive methods also need to be developed to provide the
necessary confidence for accurate predictability of the manufacturing process and mechanical part performance.
Customer interviews by Sabic identified three major hurdles
for composites introduction: design predictability, cost and
cycle time. More recently, the AVK international composites
trade organisation started an initiative to standardize composite material testing in order to build trust in reliable and
repeatable composite performance for OEMs and Tiers. This
also pointed to a need for improved design predictability.
Hybrid overmoulding process and material forms
The hybrid overmoulding process, schematically shown in Figure
1, is now well established for industrial use [3, 6].
As a composite material form, multiaxial laminates made from
constant-thickness UD tape material are most suitable for structural applications, as the UD layer directions can be best optimized
to load paths and thus are most efficient for weight saving.
Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #121 - May 2018
