Dr Alexander (Sandy) Knowles MEng, PhD, AFHEA

Dr Alexander (Sandy) Knowles

School of Metallurgy and Materials
Lecturer in Nuclear Materials
EUROfusion Researcher Grant Holder

Contact details

Address
University of Birmingham
Edgbaston
Birmingham
B15 2TT
UK

Sandy Knowles is a Lecturer in Nuclear Materials and EUROfusion Researcher Grant holder in the School of Metallurgy & Materials.

He is an experimental metallurgist focussed on the design & development of new alloys for extreme environments, including nuclear fusion, fission and aerospace gas turbines. He is a forerunner in the development of new “bcc superalloys”. Unlike current γ-γ’ nickel superalloys, β-β’ bcc superalloys make use of a bcc tungsten, titanium or steel matrix, with their higher melting points, for increased operating temperatures. This work, as well as his work on commercial alloys and ‘high entropy alloys’ (HEAs), is supported by Culham Centre for Fusion Energy (CCFE), TIMET and Roll-Royce plc.

Qualifications

  • PhD, Materials Science and Metallurgy, University of Cambridge, 2011-15
  • MEng, Materials Science, University of Oxford, 2007-11
  • AFHEA, Associate Fellow of the Higher Education Academy

Biography

Sandy Knowles graduated with a MEng in Materials Science from the University of Oxford in 2011. His master’s research project was on ‘Aluminium matrix composites with nano-ceramic particle additions’ with Prof. M. Galano linked with Materion Aerospace Metal Composites and ALPOCO, developing new high temperature and high wear resistant aluminium metal-matrix-composites.

Sandy then went on to complete a PhD at the University of Cambridge 2011-2015, on ‘Novel refractory metal alloys for ultra-high temperature applications’ with Dr. H. Stone, supported through the EPSRC and Rolls-Royce plc Doctoral Training Centre (DTC). Following this, 2015-16 he was a postdoc at Imperial College London, on the ‘Designing of Alloys for Resource Efficiency (DARE)’ grant working on ‘High strength titanium alloys’ with Prof. D. Dye.

Sandy was then awarded an EPSRC Doctoral Prize Fellowship 2016-17 to develop his “bcc superalloys” for aerospace applications. From 2017-19 he holds a EUROfusion Researcher Grant to investigate new nanostructured bcc tungsten superalloys for fusion first wall applications.

Sandy joined the School of Metallurgy & Materials at the University of Birmingham as a Lecturer in Nuclear Materials and EUROfusion Researcher Grant holder in 2018.

Teaching

Nuclear Engineering Programme Tutor

Postgraduate supervision

Sandy has two funded PhD projects available:

Refractory Metal Superalloys for Aerospace Gas Turbines, linked to Rolls-Royce and TIMET

Nanostructured tungsten alloys for nuclear fusion, supported by CCFE (ccfe.ac.uk)

Masters/summer projects 2019-20 are available on:

  • High temperature β-β’ steels
  • β-β’ chromium superalloys
  • New Zr alloys with low neutron cross-section for fission cladding and fusion neutron windows
  • High entropy alloy based investigation of metallic nuclear waste
  • Linked industrial placements with CCFE and TIMET

Research

Sandy’s research has three core activities.

  1. β-β’ bcc superalloys, focused on the design of new bcc refractory metal rich beta titanium alloys reinforced with intermetallic bcc superlattice precipitates. The alloys that have been designed and developed comprise remarkable ultra-fine bulk nano-structures and have demonstrated exceptionally high strengths. These have been demonstrated for the first time within tungsten, molybdenum and titanium ‘bcc superalloys’, with the work also extending to new high temperature steels.
  2. Titanium alloy development. Specifically on new commercial alloys in collaboration TIMET on TIMETAL 575 and 407. On TIMETAL 575, the mechanisms of Si strengthening additions are being studied using advanced electron microscopy. While detailed fatigue studies are being performed on TIMETAL 407, so as to further understand its impressive fatigue performance. Work has also investigated titanium-intermetallic composites and TWIP/TRIP alloys.
  3. High entropy alloys (HEAs), or compositionally complex alloys (CCAs), have opened up new design space for the development of advanced alloys that break away from traditional single principle element systems. The HEA approach is being used to develop new alloys with low neutron cross-section for Gen IV fission cladding and fusion neutron windows as well as ‘bcc superalloys’.

Publications

Selected publications:

  • E.L. Calvert*, A.J. Knowles* (*Equal contribution), J. Pope, D. Dye, M. Jackson ‘Novel High Strength Titanium-Titanium Composites Produced Using Field-Assisted Sintering Technology (FAST), Scripta Materialia 159 (2019) 51-57, doi.org/10.1016/j.scriptamat.2018.08.036
  • J. Gao, Y. Huang, D. Guan, A.J. Knowles, L. Ma, D. Dye, W.M. Rainforth ‘Deformation mechanisms in a metastable beta titanium twinning induced plasticity alloy’ Acta Mat, 152 (2018) 301-14, doi.org/10.1016/j.actamat.2018.04.035
  • A.J. Knowles, A. Bhowmik, S. Purkayastha, N.G. Jones, F. Guiliani, W.J. Clegg, D. Dye, H. Stone ‘Laves phase intermetallic matrix composite in situ toughened by ductile precipitates’, Scripta Materialia, 140 (2017) 59-62, doi.org/10.1016/j.scriptamat.2017.06.043.
  • A.J. Knowles, T.S. Jun, A. Bhowmik, D.N. Johnstone, T.B. Britton, F. Guiliani, N.G. Jones, C.N. Jones, H.J. Stone and D. Dye ‘A new bcc superlattice intermetallic reinforced titanium alloy system’, Scripta Materialia, 140 (2017) 71-75, doi.org/10.1016/j.scriptamat.2017.06.038.

 A full, up to date publication list can be found at: https://www.scopus.com/authid/detail.uri?origin=resultslist&authorId=56020784100&zone=