New Generation Lead-free Brass

Background

The Swedish brass industry has built up a system where most of the production is based on recycled material. During the last years, low-lead alloys have been developed and optimized through several research projects, to replace the traditional alloys containing 2-3% lead. Most efforts have been put on improving machining and productivity, as well as investigating methods to refine melt from lead. However, more stringent EU directives on lead and lead release to drinking water implies that the newly developed alloys risk not to be accepted, which poses a serious threat to the brass industry.

This project will focus on developing and modifying lead-free alloys adapted to the revised lead directives, using the learnings and outputs of the previous projects performed (e.g. the need for further developments regarding castability) as well as new studies to understand the relationship between corrosion mechanisms, alloys composition and microstructure and lead release to drinking water. Refining of brass melt from lead will also be further implemented through pilot-testing to ensure a circular approach. Finally, an analysis of carbon footprint for the different alternatives and production routes (LCA), of todays and tomorrow’s regulatory requirements, of cost consequence for the different alternatives and of testing capacities available will ensure an overall system perspective, allowing to look beyond silos and have a holistic approach in choosing the alloys and production routes to be implemented.

Objective

NEWLEAF aims to develop and optimize lead-free alloys to meet future regulations without compromising on material properties and with minimal economic and environmental impact. The alloys must be corrosion resistant ensuring reliable products with long service life and environmentally friendly as well as be suitable for efficient production processes. This alloy development should remain in a proposed circular system during the transition period towards lead-free production system without sub-optimization of any part of the circular system of the brass industry today.

Expected effects and results

NEWLEAF will produce new basic knowledge about the relation between corrosion mechanism, alloys composition and lead release to the drinking water. The investigations will give insight into alloy degradation mechanisms and will be used for optimization of both alloy and production process as well as a produce data on climate impact. Results from NEWLEAF will be relevant input to approval systems of materials in contact with drinking water on national and EU-level. Based on the results, the industry and regulators will be able to adapt to new regulations from a holistic perspective.

Partners

The work within the project is conducted in close collaboration between 8 Nordic brass companies and RISE and Swerim. The brass companies represent the entire brass value chain and life cycle, from material supplier to manufacturing companies to tool supplier.