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:

• PDF (1.03MB)

• On-line (converted to HTML by Word 97, with some "tweaks" - should be okay in most modern browsers)

• Softbound hardcopies are available on request (free of charge)

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

1. 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.
2. The industrial takeup of process modelling is very non-uniform across different materials processing sectors.
3. 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.
4. 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.
5. 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.
6. 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.
7. 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.
8. 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.
9. 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.
10. 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

11. 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.
12. 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.
13. 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.
14. 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.
15. The data needs of a modelling activity, both for input and to validate the output, should be considered (and costed) from the very start.
16. 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.
17. 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

18. 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.
19. 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

20. 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.
21. 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.
22. The EPSRC, and others running initiatives in training for universities and industry should consider whether greater emphasis can be given to materials modelling.