We report the tailoring of the microstructure of lead-free brasses with a view to improving their machinability via the controlled augmentation of the β-phase. This should be performed while keeping the mechanical properties within the EN standard, as β-phase augmentation can lead to embrittlement. Twenty seven heat treatment protocols were performed in order to transform the microstructure and consequently modify the properties of three lead-free brasses. The most successful heat treatment was chosen for each studied alloy according to the above criteria. The selected protocols led to a combination of β-phase augmentation with mechanical properties conforming to standards providing a promising ground for improved machinability performance.
This paper is part of a Themed Issue on Brass Alloys.
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