Novel Zirconium Refined Magnesium Alloys

Magnesium is the lightest structural metal. It is both recyclable and easily fabricated using standard metal production techniques. As such, magnesium alloys are highly attractive for lightweight applications in transport and other sectors. Magnesium has some unique characteristics compared to the more widely used engineering alloys such as steel or aluminium. In particular, grain refinement is critical to obtain the best performance in magnesium alloys. The most powerful grain refining effect is achieved by small additions of zirconium (Zr) but this can place limits on the other alloying additions used, since they may not be compatible with Zr.

To design improved magnesium alloys, it is necessary to better understand the interaction of Zr with candidate alloying additions. This project will use both modelling and experiment to predict the effect of joint additions of Zr and other potentially useful alloying additions in Mg-Zr-X systems (where X is a transition metal addition). In particular, a better understanding is needed of the interactions with Zr for elements that have potential to improve the corrosion performance.

The project will involve both computational modelling and experimental investigation of trial alloys. Modelling will be used to predict what phases are likely to form for given alloy compositions and identify compositions of interest. The most promising compositions will be produced and studied experimentally. Corrosion performance and microstructure will be evaluated, with the link between performance and microstructural features determined. Experimental methods will include electron microscopy to characterize microstructure, mechanical testing, and scanning kelvin probe to help understand corrosion performance.

The partner company, Luxfer MEL technologies is a UK based developer and producer of high-performance magnesium, credited with inventing more new alloys than any other company. The project will involve close collaboration with Luxfer MEL technologies researchers, based at their technology centre in Manchester. This will include the opportunity for secondment to Luxfer MEL to gain experience of undertaking research in an industrial setting.

The EPSRC Centre for Doctoral Training in Advanced Metallic Systems was established to address the metallurgical skills
gap, highlighted in several reports [1-3] as a threat to the competitiveness of UK industry, by training non-materials
graduates from chemistry, physics and engineering in a multidisciplinary environment. Although we will have supplied ~140
highly capable metallurgical scientists and engineers into industry and academia by the end of our existing programme,
there remains a demonstrable need for doctoral-level training to continue and evolve to meet future industry needs. We
therefore propose to train a further 14 UK based PhD and EngD students per cohort as well as 5 Irish students per
cohort through I-Form.

Manufacturing contributes over 10% of UK GVA with the metals sector contributing 12% of this (£10.7BN [4,5]) and
employing ~230,000 people directly and 750,000 indirectly. It is estimated that ~2300 graduates are required annually to
meet present and future growth [5]. A sizeable portion of these graduates will require metallurgical expertise and current
numbers fall far short. From UK-wide HESA data, we estimate there are ~330 home UG/PGT qualifiers in materials and
~35 home doctoral graduates in metallurgy annually, including existing AMSCDT graduates, so it is unsurprising that
industry continues to report difficulties in recruiting staff with the required specialist metallurgical knowledge and
professional competencies.

As well as addressing this shortfall, the CDT will also impact directly on the companies with which it collaborates, on the
wider high value manufacturing sector and on the UK economy as a whole, as follows:

1. Collaborating companies, across a wide range of businesses in the supply chain including SMEs and research
organisations will benefit directly from the CDT through:

- Targeted projects in direct support of their business and its future development and competitiveness.
- Access to the expertise and facilities of the host institutions.
- Involvement in the training of the next generation of potential employees with advanced technical and leadership skills
who can add value to their organisations.

2. The UK High-Value Manufacturing Community will benefit as the CDT will:

- Develop the underpinning science and advanced-level knowledge base required by future high technology areas, where
there is high expectation of gross added value.
- Provide an enhanced route to exploitation, by covering the full spectrum of technology readiness levels.
- Ensure dissemination of knowledge to the sector, through student-led SME consultancy projects, the National Student
Conference in Metallic Materials and industry events.

3. The wider UK economy will benefit as the CDT will:

- Promote materials science and engineering and encourage future generations to enter the field, through outreach
activities developed by the students that will increase public awareness of the discipline and its contribution to modern
life, and highlight its importance to future innovation and technologies.
- Develop and exploit new technologies and products which will help to maintain a competitive UK advanced
manufacturing sector, ensure an internationally competitive and balanced UK economy for future generations and
contribute to technical challenges in key societal issues such as energy and sustainability.

References:
1. Materials UK Structural Materials Report 2009
2. EPSRC Materials International Review 2008
3. EPSRC Materially Better Call 2013
4. The state of engineering, Engineering UK 2017
5. Vision 2030: The UK Metals Industry's New Strategic Approach, Metals Forum