The modification of electroless deposited Ni-P master alloy for hypereutectic Al-Si alloy

Ni-P alloy with overall composition of 7.0 wt.% phosphorus was fabricated via electroless plating on substrate of aluminum foil. The effects of this Ni-P master alloy on the modification and the processing for hypereutectic Al-20 wt.%Si alloy have been investigated. Primary silicon of hypereutectic alloy can be refined sufficiently by adding this Ni-P master alloy with total amount of 0.008 wt.% phosphorus above 800 degrees C. There is no phosphorus burning loss during fabrication of hypereutectic Al-Si alloy modifier by electroless deposition, and environment pollution is reduced. Refinement of primary silicon can be achieved with less addition and a shorter time of processing by use of this electroless deposited Ni-P master alloy as modifier. (C) 2010 Elsevier B.V. All rights reserved.