"The European Union (EU) relies on imported raw materials to manufacture renewable energy, digital, mobility, aerospace, and defence technologies. A circular economy can mitigate this critical dependency, for example by recycling materials or remanufacturing products locally. These resource efficiency strategies, however, require new supply chain configurations supported by research and innovation. While this is taking place in few selected supply chains, notably lithium-ion battery technology, little is known about circularity for most critical raw materials and their applications. Information is scattered across industry players and disciplinary competences, or not publicly available due to confidentiality concerns. This article presents a case study on titanium metal circularity in the aviation and defence sectors. The results inform three industrial policy recommendations to mitigate the risk of supply disruption in the EU, aggravated by Russia's invasion of Ukraine. Based on the case study, a methodological framework is proposed to guide future research on circularity for resource security. This subject requires urgent attention to achieve EU strategic autonomy objectives, against the background of climate change, resource depletion and waste management challenges in a complex geopolitical landscape."

Support: Digital