Microstructural evolution of intermetallic layer in hot-dipped aluminide mild steel with silicon addition

摘要: Abstract Mild steel was coated by hot-dipping into molten pure aluminum, Al–0.5 Si, Al–2.5 Al–5 Si and Al–10 (wt.%) baths at 700 °C for 180 seconds. The microstructure phase constitution of the aluminide layers were characterized means optical microscope, scanning electron microscope with energy dispersive X-ray spectroscopy, diffraction backscatter diffraction. Also, thicknesses intermetallic metal losses substrate measured to investigate interaction between mild aluminum baths. results revealed that additions silicon caused Al7Fe2Si Al2Fe3Si3 phases form above FeAl3 layer in Fe2Al5 layer, respectively. As content bath increased, thickness decreased, layer/steel interface transformed from an irregular morphology a flat morphology. decrease principally attributed detachment bath. flattened layer/mild due formation precipitates serration-like reacting containing solid-solute silicon.