Dezincification of faucets with different brass alloys

• The microstructure of brass alloy has a significant effect on dezincification. • Higher iron content (about 0.2%) increases the risk of dezincification of brass. • Low level of inhibitory substances (As, Sb) increases the risk of dezincification. • Aggressive water can induce dezincification of dezincification-resistant brass. • Real-life study on dezincification of brass alloys in different water qualities. Brass alloy is a widely used material in faucets and other components of drinking water distribution systems. Dezincification is a type of corrosion that reduces the life cycle of brass components in contact with water. It can be prevented, to some extent, by adjusting the brass composition and microstructure. The progression of the dezincification of brass components inside faucets is affected by the specific characteristics of drinking water. This study investigated the long-term impact of different drinking water qualities on the dezincification of commercial faucets. Faucet samples made of various brass alloys were exposed for 3–25 years to four different drinking water types in household use. In corrosive water, even dezincification-resistant brass showed signs of dezincification-type corrosion after 10 years of normal use. Conversely, in somewhat less corrosive water, dezincification-resistant brass performed well but non-dezincification-resistant brass experienced corrosion. In technically good-quality water, only one sample showed dezincification-type corrosion after 25 years. The research suggests that microstructure is the most critical factor affecting the dezincification of brass parts. Inhibitors, such as antimony, can also prevent corrosion to some extent. Iron in brass alloys may increase the occurrence of dezincification. Also, low alkalinity and high sulphate concentration in drinking water have a critical role in the dezincification of brass. This study provides deeper insight into how drinking water characteristics impact long-term brass dezincification in faucets, thus, offering valuable information for regulatory authorities when establishing guidelines for the use of dezincification-resistant brass in faucets.