Distribution of lead in lead-containing aluminium alloys obtained by liquid phase co-spray forming technique

Liquid phase co-spray forming (LPCSF) technique was employed to produce AI- Pb and Al-Si-Pb alloys to show that it is possible, using this technique, t o distribute lead into very fine-sized particles in Al/Al alloy matrix at l ow melt temperatures. Microstructural studies were carried out to explore t he mechanisms governing lead distribution in the matrix of the alloys durin g processing. Results showed that, regardless of the alloy compositions and experimental conditions, the microstructures of the preforms exhibited gre at similarity, i.e. less uniform distribution of Pb particles in the base r egion, and uniform distribution of fine Pb particles in the equiaxed region . During LPCSF process, the behaviour of Pb droplets was similar to that of ceramic particles, except that the shape and size of liquid Pb phase varie d corresponding to local solidification condition.