RA5a: Structure,environment and staffing policy
1. Research Structure
The Department of Materials Science and Metallurgy is host to a very wide range of research activity bounded by interfaces with Physics, Chemistry, Engineering, Biology and Medicine. It is an outstandingly successful research department with the largest number of Ph.D. students of any UK Materials Department and a consistently high level of external research funding. The Department's academic staff currently comprises seven Professors (four established chairs and three personal chairs), four Readers, and fifteen Lecturers and Assistant Directors of Research (ADRs) .
Our objectives are to produce world class graduate materials scientists and engineers, and to conduct internationally leading research into the structure, properties, manufacture and applications of materials. The work of the Department is summarised in five thematic groups described below which provide a critical mass covering the spectrum of materials research; however, all permanent members of staff lead independent research activities in their own right. The memberships of these groups at 31/3/2001 are:
Device Materials: Prof. JE Evetts, Prof. CJ Humphreys (0.5), Dr MG Blamire (Reader), Dr ZH Barber, Dr PD Bristowe (0.5), Dr BA Glowacki, Dr PA Midgley (0.5).
Materials Chemistry: Prof. DJ Fray, Dr GT Burstein (Reader), Dr GZ Chen, Dr RV Kumar, Dr JA Little.
Polymers, Ceramics and Composites: Prof. TW Clyne, Prof. AH Windle, Dr WJ Clegg (Reader), Dr PD Bristowe (0.5), Dr KM Knowles.
Physical Metallurgy: Prof. HKDH Bhadeshia, Prof. CJ Humphreys (0.5), Dr AL Greer (Reader), Dr CB Boothroyd, Dr DM Knowles, Dr JA Leake, Dr PA Midgley (0.5), Dr RC Reed, Dr ER Wallach
Biomaterials: Prof. W Bonfield, Dr SM Best, Dr RE Cameron.
This group has as its focus the understanding, development and application of functional materials: in particular, magnetic, ferroelectric, semiconducting and superconducting materials for device applications. Research is based around established facilities for very high quality thin film deposition, processing, device manufacture, measurement and microscopy. At the time of the last RAE, thin film deposition in the Department was confined largely to ultra-high vacuum deposition of metals. Since then, we have taken major initiatives in establishing other deposition techniques: major programmes on functional oxide materials and devices are supported by three pulsed laser deposition chambers served by two new excimer lasers. In 1999 the group was awarded an EPSRC grant of close to £1M to develop metal-organic chemical vapour deposition (MOCVD) of GaN and related compounds for optoelectronic applications using a new system donated by a local manufacturer (worth £0.5M). Fabrication, performed in class 100 clean rooms using both optical lithography and focused ion beam patterning and a variety of plasma and ion-beam etching techniques, is supplemented by sensitive electrical characterisation and microstructural studies of device materials and failure mechanisms.
Highlights include: the direct measurements of the electronic properties of grain boundaries in colossal magnetoresistance oxides and high temperature superconductors; the development of a novel patented process to fabricate fully textured high critical current Bi-2212 superconductors which has now been transferred to industry; work on a high-rate low-cost patented process for producing YBaCuO tape superconductors by liquid phase epitaxy; extreme nanoscale superconducting and magnetic device fabrication; the fabrication of metal-oxide heterostructure devices showing the largest tunnel magnetoresistance to date; the imaging of the p-n junctions in SiC and the magnetic microstructures of hard and soft magnets; the development of new analytical techniques including scanning transmission electron tomography and ‘image-spectroscopy’ which will allow rapid, quantitative chemical characterisation of materials at high spatial resolution; the direct calculation of defect energies in GaN, and the fabrication of blue light emitting diodes within a few weeks of commissioning the MOCVD system.
The overall aim of this group is to undertake fundamental studies on the chemical properties of materials and to find innovative solutions to industrial problems and the creation of new products. There is a substantial programme on synthesising new solid electrolytes. Electrochemistry is being used to understand and model corrosion and to define industrial scale surface processing routes such as electrograining for lithographic sheet production. There is rapidly developing programme of work on innovative electrochemistry for fuel cells for energy storage. Several programmes have been concerned with the recycling of materials and the results are finding application in several countries. High temperature oxidation is also being researched to develop materials for incinerators and inert anodes for fused salt electrowinning cells. Overall, the science has an international reputation and the innovative technologies are being exploited throughout the world with several start-up companies created in the UK.
Highlights include a new and remarkable surface treatment for stainless steel which is currently being patented; the development of several sensors for oxygen, sodium and hydrogen that are now commercially available; a new process for the addition of alkali elements to molten metals now being piloted in Germany and Belgium; a new electrochemical method for the reduction of metal oxides which should allow the many metals to be extracted more cheaply; an energy-saving method of producing lithium has been developed and is being commercialised in Taiwan for battery manufacture.
Polymers Ceramics and Composites
Work in this grouping extends from micromechanical studies of a wide range of composite and layered structures to advanced processing procedures for the development of novel and improved materials. Much of this research is based on the simulation of properties using a wide range of modelling techniques. Our extensive processing and modelling facilities enable customised materials to be produced in-house for characterisation and to validate modelled behaviour.
A major recent development has been the establishment of the Gordon Laboratory under the Directorship of Professor Clyne, which has received major funding from DERA. Work in the laboratory embraces various types of composite system (polymeric, ceramic and metallic matrices) and also foams, layered structures and surface coatings. The work involves relating microstructure to mechanical properties, and there is also considerable emphasis on novel and advanced processing techniques and on numerical modelling. These activities include enhancement of the formability of thermoplastic matrix long fibre composites via the introduction of laser-drilled microperforations, which do not compromise mechanical properties, and the development of a new technology for melt route production of metallic foams, which is currently being exploited technologically.
Ceramics research focuses on relating macroscopic properties to specific microstructural features. For example toughening through the development of layered materials for thermal shock resistance and understanding the role of interfaces and interfacial segregation in determining electronic properties. Much of this is being achieved through a coupled theoretical and experimental approach involving the state of the art atomistic and electronic modelling in combination with analytical electron microscopy. Highlights include a definitive experimental study of the process of crack deflection in ceramics; a first explanation for the role of carbon in the sintering of silicon carbide fully consistent with experimental observations; the first evidence via transmission electron microscopical techniques of a sub-nm thick sp2-bonded surface layer arising during deposition of tetrahedral amorphous carbon thin film, and ab initio modelling study of slip in TiC.
Much of the polymer research in the department is driven by computational modelling based on the development of the multiscale approach in the polymer context. Mesoscale modelling has enabled molecular simulation of polymer welding, dissolution processes and the development of liquid crystalline microstructure under flow. Both modelling and experimental aspects of the polymer programme blend into the polymeric aspects of the Biomaterials Section. A significant new theme is a programme covering the synthesis, processing, structure and properties of carbon nanotubes. Highlights include research in conjunction with Thomas Swan Ltd. which is moving towards the production of single wall nanotubes on a commercial scale; the development of a new process of surface functionalisation of multiwall tubes to enhance their solubility; the formation of nanotube / polymer matrix composites, and the demonstration of 'log-rolling' alignment under shear in the melts of certain main-chain thermotropic liquid crystalline polymers.
Physical Metallurgy research thrives in the Department, aided by many mechanisms of interdisciplinary and industrial collaboration. The goal is the creation and application of new knowledge over a large range of length scales, leading to descriptions which have predictive power and sufficient complexity to deal with industrial practice. Experimental validation is an important aspect of the work; the group has therefore invested in high-temperature X-ray analysis equipment, two thermomechanical simulators, a high-power laser, high-temperature differential scanning calorimeter, thermomechanical fatigue equipment, an orientation imaging microscope, an atomic force microscope, a large variety of computing workstations and a materials algorithms library. The major activities are in steels, nickel-base superalloys, aluminium alloys, metallic glasses and nanocrystalline alloys, multilayered structures, and intermetallic compounds.
Highlights include: diffusion measurements of unrivalled sensitivity using metallic multilayers; the discovery of very strong bainite in steels at temperatures where the diffusion distance is extremely small; the first unadjusted predictions of grain size in conventionally inoculated metallic melts; the development of poison-resistant inoculant for Al alloys; a theory for solidification including chemical ordering; the first direct observations of heterogeneous nucleation in aluminium melts; the successful, theoretical design of creep-resistant steel and nickel alloys for power generation as a technology foresight challenge; the first Avrami theory of simultaneous reactions; EELS studies of interatomic bonding in intermetallic compounds; the first thermodynamic model for particulate solutions; the creation of creep-resisting, twisted grain-structures in mechanically alloyed metals; a novel nickel-base alloy for aeroengine discs, predicted using theory; a coupled thermodynamic and kinetic model for multicomponent diffusion in superalloys; a novel, patented method of breaking up a planar diffusion-bond into an unstable interface which greatly improves the integrity of the joint and which provides a generic explanation for all transient liquid phase bonding phenomena; a new type of neural-network program, developed jointly by Prof. Bhadeshia and Dr MacKay of the Cavendish Laboratory, which has been transferred to Rolls Royce to enable them to optimise high temperature alloys; the invention of bainitic steels with the highest ever combination of strength and toughness at a fraction of the cost of equivalent maraging steels.
The appointment of Prof. W Bonfield to the new Chair in Medical materials (CCMM) in January 2000 enabled the Department to achieve its key goal of establishing a major biomaterials and tissue engineering research activity. He established the Centre for Medical Materials, based in the Department, but which is already funded with projects in association with the Orthopaedic Research Laboratory and MRC Bone Research Group in Addenbrooke’s Hospital.
The overall objective of CCMM is to progress novel biomaterials from laboratory concept to major clinical applications in patients. Major areas of research activity include calcium phosphates for skeletal implants, bioactive composites as bone analogues, bone tissue-engineering, osteoporotic bone biomechanics, biocements, phosphorylcholine surfaces for specific cell attachment, and polymers for medical devices and drug delivery. 15 PhD projects funded by EPSRC, BBSRC, and PTP are now in place across this research spectrum. Highlights in the first year of CCMM include a major IMI grant (>£1m) on polyurethanes for a range of orthopaedic, wound dressing and blood contacting applications in association with industrial partners and a substantial EU grant (>£1m) in association with 6 European universities to innovate a novel spinal prosthesis. A new bioceramics laboratory has been established and a confocal microscope facility is being formed following an EPSRC equipment grant. Other international collaborations in progress include a proposal for an Interdisciplinary Research Cluster with MIT on biomaterials and tissue engineering.
2. Research Infrastructure
The Department is equipped to an international standard, and substantial strategic development of its equipment base has been made throughout the assessment period. In addition to the specific equipment and collaborations referred to in the descriptions of the research Groups, key initiatives in supporting basic research within the department include the following:
In 1996, through IMI programme and University funding, a basement laboratory was fully refurbished as a scanning electron microscopy centre. It is now equipped with five new high grade instruments including two field emission gun SEMs.
In 1997 funding from EPSRC and the Isaac Newton Trust was obtained for a focused ion beam (FIB) system (FEI FIB200). This was the first FIB to be installed in a UK Materials Department and it has given access across the Department to ion microscopy, nanofabrication and TEM sample preparation. World-class electron microscopy supports all research in the Department. There is an extensive array of scanning and transmission electron microscopes and sample preparation equipment and researchers collaborate extensively with many other institutions in the UK and abroad and on a variety of projects, both for materials characterisation and in the development of techniques. In 1998 a new EPSRC-funded Philips CM300 field emission gun TEM was installed. This remarkably versatile and powerful instrument has been used to investigate the structure, function and composition of a wide variety of materials at the nm level.
In 1999 two grants from EPSRC enabled the purchase of a Renishaw Ramascope Raman microscope and a Princeton Measurements Corp. VSM/AGM magnetometer.
In 2000 the University used the EPSRC Strategic Equipment Initiative to create a multi-disciplinary materials characterisation facility within which the Department is hosting a high resolution X-ray diffractometer (Philips X'Pert-Pro) and a confocal scanning optical microscope (Leitz tcs sp2).
The mechanical testing facilities of the Department have been substantially enhanced during the assessment period: all the software control systems have been replaced and two new digital servohydraulic machines have been purchased and equipped with state of the art alignment facilities. A number of new creep machines have been purchased.
Within Cambridge as a whole, the general infrastructure for research is of a very high standard. The University Library and the satellite Scientific Periodicals Library are of international standard and complement the Department library. All research students are members of colleges, through which most have access to further library and IT facilities.
Computer modelling permeates and underpins much of the Department’s current materials research. Over 45 projects involving more than 50 staff and students employ and develop computer models of various kinds. The Department has developed a network of more than 100 research workstations connected over a 100 Mbit switched backbone. Several research groups have powerful multiprocessors and also use the University’s High Performance Computer Facility. The research embraces all materials classes and simulation methodologies including multiscale techniques and is leading to the commercialisation of software to the benefit of both the modelling software industry and also end-user companies.
3. Research Culture and Interdisciplinary Research
The structures of the University place the greatest emphasis on excellence in research potential and achievement. For example, research achievement at the highest level remains paramount in the promotion of individuals to Readerships or Professorships. Examples of formal interdisciplinary structures which are in place are the IRC in Superconductivity which continues to provide a focus for research on superconductivity in Cambridge and the Cambridge Centre for Medical Materials which has been established to promote links to the clinical and biological subject areas. The electron microscopy in the Department supports a wide range of interdisciplinary activities spanning Physics, Chemistry, Engineering and Biology. An interdisciplinary project has recently been initiated within the Cambridge MIT Institute scheme (involving the Engineering Department in Cambridge and 3 Engineering Departments in MIT), which is aimed at the development of a novel ultra-light steel sheet material, comprising thin faceplates and a core incorporating steel fibres. The Department is strongly represented in recent multi-disciplinary applications from Cambridge University to EPSRC for a Nanotechnology IRC and to the Leverhulme Trust for a centre for fundamental materials research.
Each staff member is appraised in confidence every two years by the Head of Department. Sabbatical leave, of one term in seven, is a right of University Officers and is spent pursuing dedicated research. Each research group has a programme of regular research meetings in addition to Departmental Colloquia. Unestablished research staff are regularly appraised. The progress of research students is regularly monitored through written reports every year from the supervisor to the Board of Graduate Studies. An examined dissertation (typically 10000 words long) is presented at the end of the first year. In the first year students must also attend a number of examined techniques courses and present a seminar on their research work. The University encourages research students to become involved in undergraduate teaching either through practical demonstration or small group supervision. The very high demand for our students and post-docs is illustrated by the list of those who have moved to University Lectureships during the assessment period: Dr P.D. Brown (Nottingham), Dr C.A. Dandre (Swansea), Dr H. Fujii, (Osaka), Dr A. Korsunsky (Newcastle), Dr J.D. Robson (Swansea), Dr T. Warner (Odense), Dr J.M.K. Wiezorek (Pittsburgh).
4. Applied Research and Technology Transfer
The Department places great emphasis on the attraction of external sponsors to support its research programme and to spin-off new discoveries to industry wherever appropriate. A major example demonstrating the interdependence of basic research and commercial development is the development of a new technology for the reduction of metal oxides by the Materials Chemistry Group [Nature 407, 361 (2000)]; a new company (British Titanium plc) has been set up to exploit this method for producing low cost titanium in association with the University. Licences for other metals with other producers are currently under negotiation. Similarly, the study of strong/porous interlayered ceramics originally pioneered by Dr W.J. Clegg while at ICI [Nature 347 455 (1990)], has led to substantial direct funding for his research under the Synergy Ceramics programme by NEDO, Japan. Several academics in the Department have recently established 2-3 year collaboration projects with ABB in the areas of coated superconductors, electron spin injection devices and laser beam welding; the total funding is around £380k as part of a framework agreement set up between ABB and the University.
During the assessment period the Department has led two major Foresight Challenge collaborations:Since RAE1996 three staff been recruited to chairs elsewhere: Dr P.J. Withers to the Manchester Materials Centre (1997), Dr S.B. Newcomb to the University of Limerick, Dr I.M. Hutchings to the Cambridge Engineering Department (2000). During the assessment period Dr R.E. Somekh joined Plasmon Data Systems as senior research manager (1997), Dr G. Goldbeck-Wood re-joined Molecular Simulations International; Dr W.M. Stobbs died in 1996. High quality appointments have been made to replace these staff: Dr P.A. Midgley, Dr Z.H. Barber, Dr R.V. Kumar and Dr R.C. Reed to University Lectureships to ensure continuity of research in the fields of electron microscopy, thin film deposition, materials chemistry and physical metallurgy respectively; Dr T.J. Matthams and Dr G.Z. Chen as ADRs supported on outside funds to develop research in polymer composites and electrochemistry respectively. Dr S.M. Best was appointed to a lectureship to support Prof. Bonfield's work in biomedical materials.
(1) "Designing Materials for Aerospace and Power Plant: a Revolutionary Computer modelling approach" OST provided £1.4M via the EPSRC to fund this work with further industrial support worth £2M from companies including Rolls Royce, Special Metals, Corus, Alstom, Mitsui Babcock, Thermotech and Rockfield Software. Achievements include a new alloy that meets the targets for steam plant and which is currently under further tests.
(2) "Modelling of polymeric materials and processing" in collaboration with Leeds University and the Cambridge Department of Physics. OST provided a challenge award of £1.03M with a further £1.3M being raised from industrial collaborators including TWI, Courtaulds, ICI, London International Group, Unilever, Molecular Simulations (MSI), Oxford Materials.
Where a particularly close collaboration has been developed with industrial partners the Department has developed a series of Embedded Industrial Laboratories
(1) Innogy plc, have funded the establishment of a new laboratory for the study of new materials for innovative electrochemistry, in particular fuel cells for energy storage to be directed by Prof. Fray.
(2) In 1994 Rolls-Royce selected the Department to contain its University Technology Centre in nickel-base superalloys for turbine blades and discs. This Centre has gone from strength to strength and currently contains 31 people (Academic staff, post-docs and research students), and the research is supported by substantial grants from the EPSRC, Rolls-Royce, Europe and other sources.
5. Staffing Policy and Staff Changes since the last RAE
Academic excellence is the paramount consideration in the selection of new academic staff. While fixed term ADRs are appointed to fulfil specific research requirements, advertisements for Lecturers and Professors are drawn sufficiently widely to allow the appointment of the highest calibre applicants irrespective of their precise research field. Formal Department teaching loads are reduced for newly appointed staff, enabling them to focus on research activities. It is Department policy to favour recently appointed staff and research fellows in the allocation of research studentships and support from the Department's annual equipment budget. The Department has also established a mentoring scheme in which a designated senior member of the Department in a different Research Group provides informal guidance to assist in establishing research activities.
Copyright 2002 - HEFCE, SHEFC, ELWa, DEL
Last updated 17 October 2003