I
have been set the onerous task of helping you, a potential
student, on choosing a field of study. This is a decision
that will influence the rest of life and so should
not be taken lightly. It is not possible to predict
what specific skills will be in demand over your 40
to 50 year working life, so may I suggest you choose
a "Core" rather than a specialist skill
and be flexible as opportunities emerge.
Materials
Science is at the centre of almost all that we do
and possess. We live in a society in which we expect
year on year improvement in the products we buy and
our overall standard of living. At the same time we
have expectations of increased safety and reliability,
less pollution and more energy efficiency. In all
these areas Material Science is either the prime driver
or in very close support of another technology.
It
is worth mentioning a few examples, as very often
the reason for the improvement is not obvious to the
user:
Cars
are more economic, quieter, accelerate better and
much more reliable than twenty years ago. Just a few
of the reasons are stronger steels, the introduction
of composite materials, higher temperature materials
in engines, printed circuit boards, materials that
are tailored to behave dynamically in crashes and
to dampen vibrations.
We
can now fly with unprecedented safety and reliability
to almost anywhere in the world for less than the
average UK weekly wage. This is due almost entirely
to better materials, without which it would not be
possible to make bigger and more economic aircraft.
This is a good example of the rather simplistic "Cubed
/ Squared Law". If one considers the task of
building an aircraft of twice the size of its predecessor
one could predict, using the same design and materials,
its weight to increase by 8 (= 23 ) times. However
the cross sectional area of the undercarriage legs
will increase only by 4 (= 22 ) and the stress in
the undercarriage will double. Material Science has,
over the last few decades, provided the solution to
this. Firstly directly by producing better steels
for the undercarriage leg but more importantly by
developing composite materials that have allowed designers
to break away from the "cubed" part of the
Law. Nobody, since Howard Hughes has tried to double
the size of aircraft in one step. However if you compare
a De Havilland Comet with the Airbus A380 that is
just about what we have achieved in a few decades.
The
other unnoticed improvement in aircraft is in the
engines. These deliver much higher thrusts, at lighter
weight and using less fuel. This is attributable to
a large extent to higher operating temperatures and
more complex blade profiles, both of which have only
been possible due to better materials and processes.
At the same time reliability has been raised to a
level that most of the aircraft flying the Atlantic
have only two engines.
Bridges
are having their strength increase, to take more and
heavier lorries; very often by bonding carbon fibre
laminates to the existing steel reinforced concrete
structures. (In themselves an earlier example of a
"Composite" material)
Wind
turbines blades are continuing to get bigger and this
is increasing the stresses in the blades and hence
the requirements for the materials used. Progressively
Glass and Carbon woven into Non-Crimped Fabrics and
impregnated by Resin Infusion Processes are replacing
the Wood and Wet lay-up composites currently used
by many producers.
What
direction will Material Science take in the future?
The current trend of reducing scale and increased
complexity will accelerate. In the 1950's load bearing
materials were almost all metals, which were assumed
to be homogeneous with only minor directional variations
in forgings and rolled plate. One occasionally looked
at the grain structures in an optical microscope but
only if one had an unexpected failure.
Today
it is normal to use carbon and glass fibres, in a
polymer matrix to design structures where strength
and stiffness can be independently tuned in three
directions. The helicopter rotor blade is a good example.
Here bending stiffness in two directions plus torsional
stiffness have to be independently tuned to complex
dynamic requirements, in a structure that strong enough
to survive 25 years of military operations, in rain
and sand with the occasional lightening strike. This
is achieved with a complex mixture glass and carbon
fibres, laid at difference angles, supplemented with
bonded titanium
For
tomorrow one can see an increase in the number of
materials being used in complex combinations. In particularly
the use of "Surface Science" to add thin
layers of critical materials to overcome weakness
in the bulk structure, such as wear and erosion resistance
or electrical and chemical properties. One can envisage
structures with several different fibre types, with
regional gradation between rigid and elastomeric matrices
and made to meet diverse requirements, by depositing
layers a few microns thick of very exotic elements.
Electron beams, controlled to optimise the cure process
in different areas of the same part, may then cure
the structure. The challenge will not only be to design
and make such structures but to develop the methods
to certify and qualify the materials used.
The
other area for the future is the really small-scale
developments with Nano Fibres only a few nanometers
in size, where the limits will be the size of molecules
and our ability to see and manipulate at this scale.
My difficulty of perceiving how much of this will
be applied to real products is matched by my conviction
that progress will be rapid and lead to unexpected
opportunities. There are excellent opportunities here
for newly qualified Materials Scientists as most of
the current practitioners, such as myself, are very
ignorant of the technologies in this field.
The
most important advantage of joining the Materials
Science community is not just the Technology but the
people whom you will meet, who will help you and whom
you will help. I would like to suggest that you join
SAMPE (Society for the Advancement of Materials and
Process Engineering). It is an international group
of Material Scientists and Engineers, who have helped
me and given me many enjoyable opportunities. It strongly
supports the Student Community with events in Europe
and the USA. Prizes of free attendance at the European
and US conferences are given to the best students.
Student fees are only 20 Euro per year, if you wish
to receive details, please contact:
Ir.
Adrie Kwakernaak ( akwakernaak@compuserve.com)
Uranusstrat 3
NL-1431 XH Aalsmeer
The Netherlands
Or
visit our Website: http://www.sampe.com
Finally,
whatever you finally select as your course of study
you should have too objectives:
1.
Make a significant contribution to the improvement
of the products and society with which you will work.
2. Have fun
I
believe that Materials Science and Engineering offers
you the opportunity to do both
Bob
Griffiths
Vice
President, SAMPE Europe.
bobgriffiths@btinternet.com