AWWA WQTC64037

In an effort to comply with the requirements of NSF Standard 61, sections 8 and 9, manufacturers investigated a number of new processes and materials. This paper discusses the opportunities and challenges presented to manufacturers with the use of copper alloys with lower lead content. Many copper and brass alloys, with very low lead content, have been known to metallurgists for decades. However, none of these alloys possessed the properties necessary to effectively fabricate them into components for valves, meters and faucets. A number of new cast alloys were developed to help manufacturers meet these NSF requirements. An industry consortium of the Copper Development Association (CDA), Brass and Bronze Ingot Manufacturers (BBIM), the American Foundrymen's Society (AFS), and the Materials Technology Laboratory of CANMET in Canada conducted research and developed a series of copper alloys which use bismuth and selenium as replacements for lead (commercially available as EnviroBrass® also known as SeBiLOY®). The Federal Metal Company has concurrently developed a group of proprietary alloys containing bismuth and lanthanides (commercially available as FederAlloy®). Silicon brass alloys have been developed as replacements for traditional leaded alloys and alloy C89836 has been developed and commercialized using bismuth but without selenium. No lead is added to these alloys, and the minimal amount of lead present is due to the lead contained in recycled materials and ore that are used as the source metals. These alloys are formed by substituting bismuth, selenium or silicon for lead, to enhance the machinability and self-sealing characteristics that are the desirable consequences of lead addition. Bismuth is used because it behaves similarly to lead in the manufacturing process and selenium is used to enhance the effects of bismuth. There are a number of issues impacting manufacturers who utilize these alloys to create a variety of drinking water components as described in this paper. Includes 14 references, tables.