Dezincificationresistant

Dezincification-resistant, often abbreviated as DZR, refers to copper-based alloys engineered to resist dezincification, a corrosion process in which zinc is selectively leached from brass when exposed to certain waters, particularly those that are chloride-rich or acidic. This selective dissolution leaves a porous, copper-rich structure that weakens the material.

Most DZR brasses achieve resistance by lowering zinc content and/or adding alloying elements such as tin, nickel, phosphorus, silicon, or aluminum. These additives help stabilize the alloy’s microstructure and promote protective surface films that inhibit zinc dissolution, reducing the risk of dezincification in aggressive water environments.

DZR alloys are commonly used in plumbing and water-supply fittings, valves, hydrants, and hot-water components where water chemistry can promote dezincification. They are favored in potable water systems and in marine or reclaimed-water applications where exposure to chloride-containing waters is a concern.

Assessment of dezincification resistance is typically performed through laboratory tests that simulate aggressive water conditions and environmental exposures. Compliance with relevant potable water standards is often required to limit metal release and ensure consumer safety.

Considerations for use include cost and variability in machinability or mechanical properties depending on processing and heat treatment. While DZR offers improved resistance in challenging water conditions, system designers must evaluate water chemistry, temperature, and operating pressures to ensure long-term performance and compatibility with other materials in the installation.