Cold shut formation analysis on a free lead yellow brass tap

In order to minimize the risk of the lead in the health, the chemical composition of the plumbing components have suffered changes. However, lead improves machinability and castability in copper alloys. In this work a failure created during solidification process on a lead free tap of yellow brass alloy was investigated. Visual inspection, SEM, EDS and a ProCast V.2008 simulation were carried out in order to determine the cause of this failure. The results exhibited a close correlation between the failure formation and a convergent metal flow and solidification involved during the tilt process and determines that failure was caused by a cold shut, also inclusions carrying from the core and metal oxide films were also found.