Investigation of intermetallics in die-casting sludge

Abstract

A study into the intermetallic sludge found at the bottom of an AZ91D, an AM60B and an AM50A die-casting furnace was undertaken using an SEM and an electron microprobe. The results indicate that the composition of intermetallics is consistent with Al(Mn,Fe) although the range of Al and Mn tends to vary depending on the alloy. The particles are Mn rich as opposed to Fe rich. The majority of the particles are less than 50μm in size though they appear to group in clusters and coarsen. Mechanisms for the formation of the sludge are discussed including the coarsening and settling behavior of the particles. Recommendations for reducing the quantity of sludge are made