Corrosion–microstructure interrelations in new low-lead and lead-free brass alloys

ABSTRACT

Stress-relieving heat treatment has been reported to deplete the corrosion resistance of new low-lead and lead-free brass alloys. How the heat treatment, processing and material composition relates to the microstructure and corrosion performance is not well understood. The present study aims to fill this knowledge gap by mapping stress-relieving annealing conditions and different standardised compositions to their respective microstructures and dezincification performance. It was found that loss of corrosion resistance was only the most severe for alloys with higher aluminium and iron content. These alloys displayed significant precipitation of intermetallic aluminium arsenide particles on grain boundaries, twins and lead particles, as well as the formation of β-phase along grain boundaries.

This paper is part of a Thematic Issue on Copper and its Alloys.

KEYWORDS:

• Brass
• corrosion resistance
• lead
• beta-phase
• particles
• arsenic
• aluminium
• simulation

Acknowledgements

The authors of the present study would like to thank Nordic brass Gusum AB for support and valuable discussions throughout the work as well as the Swedish Governmental Agency for Innovation Systems (VINNOVA) for financial support. In addition, the authors thank Bevis Hutchinson for reviewing the paper.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was partly supported by the Swedish Governmental Agency for Innovation Systems (VINNOVA) for financial support [grant number 2016-01994].