New and improved steels...
Our research is focused on ways to develop new and improved steels. Our team is working on physical-chemical topics relating to iron and steel manufacturing and usage, tackling both fundamental and applied research, from steelmaking, through to production e.g. casting, forming, coating and joining, and product performance.
The properties of steel are strongly influenced by its microstructure, therefore it is essential to understand, predict and monitor the development of microstructure during steel processing. Research into microstructure and thermo-mechanical processing is led by Professor Claire Davis.
We're working on understanding the role of casting and reheating, when used, on microstructure development, with microalloying element segregation and grain growth being of particular interest. Consideration of the hot deformation processes, for example thermo-mechanical controlled rolling and forging, through the role of alloy content, strain and temperature on recrystallisation and grain size development, are major research activities. In alloy steels heat treatment and precipitation reactions after hot deformation are also important in controlling the final mechanical properties, with thermo-dynamic and kinetic models being used to predict precipitation.
A complementary activity is the development of non-contact, non-destructive evaluation techniques for steel microstructure characterisation. Electro-magnetic (EM) sensors can monitor changes in magnetic permeability and electrical resistivity, which are sensitive to changes in microstructure in ferro-magnetic materials. We are interested in understanding the relationships between EM sensor signals and steel microstructural parameters for a range of potential applications. This work is carried out in collaboration with researchers at the University of Manchester, developing new EM sensors, with the work having resulted in systems being installed in steel mills and being trialled for steel product characterisation.
We also undertake research into coatings for steel. Applications for steels can range from advanced functional coatings to industrial coatings, such as those used for galvanising and electroplating sheet steels or for lamination-coating electrical steels. Research in this area has focused on coatings such as aluminium, titanium and nickel alloys.
Our research investigates the relationship between microstructure, processing and properties in alloys. Engineering steels and alloys operate in challenging conditions, often under extreme temperatures while under load. Research includes understanding not only how the surface of the alloy degrades, by processes such as oxidation, but also how these changes alter the underlying microstructure which can affect the overall steel performance. Current studies examine the behaviour of alloys in reducing and oxidizing environments as well as extending the observations to dwell fatigue and fretting. In order to understand the mechanisms of oxidation, including anion and cation fluxes, isotopic tracers and secondary ion mass spectrometry (SIMS) is used alongside electron microscopy techniques.
Key research findings have included elucidation of oxygen and hydrogen transport during oxidation of superalloys and zirconium, the role of rare earth elements in oxidation, and the development of novel methodologies combining electron and ion-based analysis techniques.