Development of strong, formable, stainless and low-cost magnesium alloys for next generation cars

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Light weighting is one of the biggest challenges facing manufacturers today and urgently required for next generation cars to increase fuel efficiency and reduce carbon emissions. Reducing a car's weight by 50 kg decreases emissions by up to 5g CO2/km and increases fuel economy by up to 2%. Being 75% and 33% lighter than steel and aluminium (Al), Mg is becoming more popular with automotive engineers. In theory, Mg alloys offer a promising solution for lightweighting in several industrial sectors. However, Mg components currently only constitute ~1% of a typical car's weight. This is attributed to long-standing issues with Mg alloys such as high production cost, low formability and high corrosion rate, compared to heavier Al and steels. Therefore, designing high performance and low cost Mg alloys is in great demand for automotive industry. Producing strong, formable, stainless and low-cost Mg alloys is recognised to be extremely difficult and has not to date been achieved. Traditional alloy design routes and manufacturing processing are not only time-consuming and not cost-effective, but also cannot guarantee production Mg alloys with high performance. In addition, the highly debated recrystallisation and deformation mechanisms, critical in optimising mechanical and physical properties of Mg alloys, need to be thoroughly explored and established.The overall objective of this fellowship is to develop new routes of alloy design, simultaneously developing innovative manufacturing processes, thereby producing strong, formable, stainless and low-cost Mg alloys(e.g., yield strength >300 MPa, Index Erichsen (I.E.) value indicating stretch formability >8mm, corrosion rate <0.4mg/cm2/day). This will be achieved by understanding how the alloying elements interact with each other and how the developed processes can be used to tailor multi-scale microstructures (e.g., alloys containing ultrafine grains (~1 microns) with weak texture). Equipped with vast state-of-the-art facilities covering alloying designing, manufacturing and processing, testing and characterisation, Royce@Sheffield and Sorby Centre will help me deliver a step change in the discovery and development of new Mg alloy systems, enabling concepts development from early, fundamental research right through to translation to industry and, crucially, covering Technology Readiness Levels (TRL) 1 to 6. Recently, a corrosion-resistant Mg-Li alloy was produced, but its high production cost and potential flammability still need to be considered before it can be commercially adopted. My goal is to push the boundaries of high-performance light Mg alloys yet further and I already have evidence that I can increase the strength and corrosion resistance of a commercial Mg alloy, currently approved by U.S. Federal Aviation Administration, without ductility loss using novel thermomechanical processing. This fellowship will address significant challenges in coupling high mechanical properties and corrosion resistance within a single alloy system.The fellowship aims to help industrial project partners accelerate the development of new advanced light alloys. New thermomechanical/manufacturing processes are exportable technology and will permit companies to develop new IP. My research will be further extended to develop products for aerospace, public transport and medical industries and ensure a low carbon economy in the UK. Most importantly, this fellowship will assemble a new UK team of engineering and microscopists with the aim of turning vulnerable Mg into reliable structural/medical materials, thereby accelerating the pace of light weighting in several industrial sectors.