Title: The Effects of Superheating Treatment on Distribution of Eutectic Silicon Particles in A357-Continuous Stainless Steel Composite,
Abstract: In the present study, superheating treatment has been applied on A357
reinforced with 0.5 wt. % (Composite 1) and 1.0 wt.% (Composite 2) continuous
stainless steel composite. In Composite 1 the microstructure displayed poor
bonding between matrix and reinforcement interface. Poor bonding associated
with large voids also can be seen in Composite 1. The results also showed that
coarser eutectic silicon (Si) particles were less intensified around the
matrix-reinforcement interface. From energy dispersive spectrometry (EDS)
elemental mapping, it was clearly shown that the distribution of eutectic Si
particles were less concentrated at poor bonding regions associated with large
voids. Meanwhile in Composite 2, the microstructure displayed good bonding
combined with more concentrated finer eutectic Si particles around the
matrix-reinforcement interface. From EDS elemental mapping, it was clearly
showed more concentrated of eutectic Si particles were distributed at the good
bonding area. The superheating prior to casting has influenced the
microstructure and tends to produce finer, rounded and preferred oriented
{\alpha}-Al dendritic structures.