Modelling of Materials
and Processes
A review of activity and needs
in the UK in response to the
Technology Foresight exercise
Dr H.R. Shercliff
Cambridge University Engineering Department
The full report is available in the following
formats:
Synopsis
Motivation for the Report
This report presents a review of
materials modelling commissioned by the Institute of Materials (IoM)
and Office of Science and Technology (OST), in view of the high
profile given to materials modelling in the recommendations of
the Technology Foresight exercise published in 1995.
The initial purpose of the report was to
serve as a "position paper" for the IoM in its
discussions of how to carry the Foresight objectives forward in
this area. The overall aim is to promote the development of
physically-based, industrially-useful models. Opinions have been
sought by interviews and questionnaires, and from the published
literature.
Given the importance of materials
research, and modelling in particular, within current initiatives
from EPSRC, DTI and other funding agencies, the report should be
of interest to a wide community: government and other funding
agencies, industrial and academic modellers, experimentalists who
measure data intended either as input for models or for model
validation, materials scientists and manufacturing process
engineers, including managers responsible for modelling
activities.
Materials modelling covers a vast range
of activity - this is reflected in the responses to the
questionnaire coming from fields as diverse as geological
sciences, molecular modelling and high velocity impact, though
the majority relate to work in the more traditional materials
processing industries. The review has focused on "structural"
materials - predominantly metals, polymers and composites. Within
these classes of materials, consideration has not been given to
extractive processing which falls within the remit of process and
chemical engineering. "Functional" materials (semiconductors,
superconductors, magnetic and optical materials, biomaterials etc)
have also not been considered, nor have the less obvious "material
processing" sectors such as food production. This
selectivity is not intended to deny the importance of modelling
in these areas, but is simply to keep the review manageable. Some
opinions have been offered from these other areas of activity,
and a number of the dominant issues will doubtless be familiar to
those working in these areas. Separate studies would be required
to highlight the more specific details which relate to the very
different physical behaviour and industrial context of these
areas.
This survey builds on an earlier study (Sargent, Shercliff and Wood, 1993) for the ACME Directorate of SERC, which
considered almost exclusively metals manufacturing processes. The
scope has been widened to non-metals, and consideration also
given where possible to modelling of material performance in
service. Expanding on the conclusions of the previous report,
several key issues are raised concerning research priorities in
materials modelling, the potential for greater academic-industrial
collaboration, and training and educational needs in the UK.
Section 1 of the report summarises the
relevant aspects of the Technology Foresight documents, and the
response from the EPSRC. Section 2 discusses general issues and
needs in materials modelling, while Section 3 provides more
detailed comments on a number of key materials or process areas.
Section 4 summarises with overall Conclusions and Recommendations.
The earlier report, Modelling Materials Processing, can be viewed on-line; softbound hard copies
are available on request (free of charge).
Summary of Main Conclusions
General industrial and academic
perspectives
- The importance attached to
materials modelling by Technology Foresight is fully
endorsed by this survey of structural materials.
Modelling also merits deeper consideration in extractive
processing, building materials, functional materials, and
food processing.
- The industrial takeup of process
modelling is very non-uniform across different materials
processing sectors.
- Most research activity and software
is only accessible to large high-technology companies. A
significant impact in SMEs requires more well-packaged PC-based
software.
- Centres of excellence in each
industrial sector are needed to offer advice and training
in modelling, to transfer expertise to industry (particularly
SMEs), and for benchmarking software.
- Modelling has a major role to play
in Design for Manufacture by bringing processing into
design at an appropriate level of complexity. Routine use
of modelling can also benefit the overall efficiency of a
manufacturing system.
- Industrial modelling problems are
no less demanding academically than purely scientific
research. Defining research priorities in materials
modelling requires input from both academics and
industry, with scope for greater collaboration in every
industrial sector.
- Academic modelling too rarely leads
to usable software for industry, but implementation in
software should largely be the role of intermediate
research organisations or spin-off companies.
- Some academics comment that
collaborative research and software output do not receive
sufficient credit in Research Assessment Exercises, and
that collaboration in modelling at the European level is
also under-rated by funding agencies.
- Multi-physics modelling and linking
length scales are popular current themes. The benefits of
adding greater complexity should be carefully argued for
a given process or material problem.
- Molecular calculations are making
good headway in polymers. The best potential for
atomistic methods in other materials appears to be for
interfaces and surface behaviour, and for electronic
materials.
Aspects of model building
- Computational power is
not an issue except for certain complex 3D processing
problems, or the most ambitious research process models.
Increased computer power is absorbed far too readily in
added complexity, rather than in more thorough use of an
existing model.
- Choosing the appropriate level of
complexity is an essential element of all model building
and use, and both analytical and numerical methods should
be exploited.
- FE methods are largely very mature,
and further development would offer only modest benefit
at present. Much more can be achieved by integrating
microstructural and damage modelling with FE, in order to
track the product state through multi-stage processing
and service.
- Software engineering developments
are needed to enable smoother data transfer from design
to production. Models are increasingly the basis for
communication between suppliers and customers in industry.
- The data needs of a modelling
activity, both for input and to validate the output,
should be considered (and costed) from the very start.
- The new DTI MMP programme on
measurement of materials parameters for processing
rightly emphasises the importance of modelling. There is
a need to make non-proprietary data for processing more
widely available.
- Interface properties, in particular
friction and heat transfer, are critical in all materials
process modelling. There is a need for research on micro-modelling
of interfacial conditions, and the coupling of these
models to macroscopic FE computations and to experiment.
Networking
- There is scope for more
UK workshops covering a range of modelling activities, to
promote collaboration. There is support for a well-organised
directory of UK modelling activity, both on the Web and
on a free CD.
- Worldwide activity in materials
modelling is very great - an international science-watch
is very important in this field. The Web is not uniformly
viewed as an efficient route to obtaining reliable
information on modelling work.
Education and training
- Materials modelling is a
key area to develop in degree courses at undergraduate
and postgraduate level, combining materials science and
engineering, numerical methods and software engineering.
- The principal requirement in
training modellers is establishing the right attitude, i.e.
an open-minded approach, the ability to function in a
team, and a clear view that a model is a tool to reach an
end rather than an end in itself.
- The EPSRC, and others running
initiatives in training for universities and industry
should consider whether greater emphasis can be given to
materials modelling.