5/14/2024
Melting and raw materials
Sustainability & CO2 neutrality
Interview
Research project: Making better use of recycled aluminium
Hanka Becker has received two million euros in funding from the German Research Foundation's (DFG) Emmy Noether Programme for her research into the recycling of aluminium. From mid-2024, she will lead a research group at Otto von Guericke University Magdeburg, which is investigating how impurities in the material can be tolerated harmlessly. We spoke to the scientist about what her research findings could mean for the foundry industry, among other things.
What are – as things stand today – the problems with the production and use of recycled aluminium?
Hanka Becker: When aluminium and its alloys are recycled, impurities such as iron are introduced. Among other things, these lead to the formation of intermetallic phases which, in combination with the impurity elements, the alloying elements and the aluminium, are present in the material as particles enclosed by the aluminium. Depending on the nature of the particles, these can lead to the formation of further defects in the workpiece during the manufacturing process and have a negative impact on a wide range of application properties.
What is your research approach and how did you manage to convince the DFG of the merits of your project?
Becker: The aim of the research project is to use innovative grain refiners to adjust the microstructure, including the intermetallic phases, in such a way that the impurity elements can be tolerated or even utilised without any disadvantages. Grain refiners are particles that are added to the melt before solidification and that influence the formation of the internal structure, for example the microstructure, of the material during solidification.
The production, effect and use of the new grain refiners, including the resulting properties of the designed aluminium alloys, are being investigated on a fundamental scientific basis. The project is also about fundamentally understanding the background. Perhaps it was the scope, the vision and potential for the environment and the economy and the good planning of the project that convinced the DFG.
To what extent can the environment benefit from your work?
Becker: The production of primary aluminium accounts for 3 percent of total greenhouse gas emissions. That is 15 per cent of emissions in the industrial sector, as Professor Dierk Raabe and others have reported. This means that a large proportion of global energy production is used for the production of primary aluminium alone. Compared to the use of primary aluminium, the production of secondary aluminium or recycled aluminium requires only 5 percent of the energy.
At the same time, the availability of secondary aluminium is increasing, as many products are reaching the end of their service life. It is estimated that the amount of recycled aluminium will double in the first half of this century. In terms of sustainability, resource conservation and energy efficiency, the environment will benefit from advances in the recycling of aluminium and aluminium alloys without any loss of quality.
How will die-casting foundries and other aluminium processors in Germany and elsewhere benefit from the findings of your research? When will this be possible?
Becker: An important goal is that results from the basic research project can be applied. The research results are made available to colleagues from research and development through scientific publications and national and international conference and meeting contributions. At network meetings with experts from industry, we will discuss the requirements for the usability of the findings for foundries and aluminium processors.
Furthermore, when the first research results are available, I hope to apply for and start a knowledge transfer project with an industrial partner from the DFG or another funding organisation during the Emmy Noether project so that society can benefit from the findings in a timely manner.
About Hank Becker
Hanka Becker studied materials science and materials technology at the TU Bergakademie Freiberg. She also completed her doctorate there in 2018. During this time and a subsequent postdoctoral phase, she spent research periods at the Norwegian University of Science and Technology, Trondheim, and at the Technical University of Denmark, Lyngby. Following her success in the Emmy Noether Programme, she moves to the Institute of Materials and Joining Technology at Otto von Guericke University Magdeburg.
Hanka Becker: When aluminium and its alloys are recycled, impurities such as iron are introduced. Among other things, these lead to the formation of intermetallic phases which, in combination with the impurity elements, the alloying elements and the aluminium, are present in the material as particles enclosed by the aluminium. Depending on the nature of the particles, these can lead to the formation of further defects in the workpiece during the manufacturing process and have a negative impact on a wide range of application properties.
What is your research approach and how did you manage to convince the DFG of the merits of your project?
Becker: The aim of the research project is to use innovative grain refiners to adjust the microstructure, including the intermetallic phases, in such a way that the impurity elements can be tolerated or even utilised without any disadvantages. Grain refiners are particles that are added to the melt before solidification and that influence the formation of the internal structure, for example the microstructure, of the material during solidification.
The production, effect and use of the new grain refiners, including the resulting properties of the designed aluminium alloys, are being investigated on a fundamental scientific basis. The project is also about fundamentally understanding the background. Perhaps it was the scope, the vision and potential for the environment and the economy and the good planning of the project that convinced the DFG.
To what extent can the environment benefit from your work?
Becker: The production of primary aluminium accounts for 3 percent of total greenhouse gas emissions. That is 15 per cent of emissions in the industrial sector, as Professor Dierk Raabe and others have reported. This means that a large proportion of global energy production is used for the production of primary aluminium alone. Compared to the use of primary aluminium, the production of secondary aluminium or recycled aluminium requires only 5 percent of the energy.
At the same time, the availability of secondary aluminium is increasing, as many products are reaching the end of their service life. It is estimated that the amount of recycled aluminium will double in the first half of this century. In terms of sustainability, resource conservation and energy efficiency, the environment will benefit from advances in the recycling of aluminium and aluminium alloys without any loss of quality.
How will die-casting foundries and other aluminium processors in Germany and elsewhere benefit from the findings of your research? When will this be possible?
Becker: An important goal is that results from the basic research project can be applied. The research results are made available to colleagues from research and development through scientific publications and national and international conference and meeting contributions. At network meetings with experts from industry, we will discuss the requirements for the usability of the findings for foundries and aluminium processors.
Furthermore, when the first research results are available, I hope to apply for and start a knowledge transfer project with an industrial partner from the DFG or another funding organisation during the Emmy Noether project so that society can benefit from the findings in a timely manner.
About Hank Becker
Hanka Becker studied materials science and materials technology at the TU Bergakademie Freiberg. She also completed her doctorate there in 2018. During this time and a subsequent postdoctoral phase, she spent research periods at the Norwegian University of Science and Technology, Trondheim, and at the Technical University of Denmark, Lyngby. Following her success in the Emmy Noether Programme, she moves to the Institute of Materials and Joining Technology at Otto von Guericke University Magdeburg.