Effects of air atomisation,spray deposition and melt overflow techniques on microstructural features of Al–Fe–V–Si alloy

Abstract

Microstructural features of atomised powders, spray deposited preforms and melt overflow strips of 8009 series AlFeVSi alloy were investigated to reveal the microstructural evolution associated with the processing condition variations. X-ray diffraction (XRD), optical microscopy and scanning electron microscopy (SEM) techniques were used to identify the crystal structures of dispersoid phases in the specimens. The primary intermetallic phase was characterised as bcc α-Al(Fe,V)Si having a lattice parameter in the range 12·51–12·53 Å, other phases are identified as icosahedral, Al₃Fe and Al₁₃(Fe,V)₄ by XRD. SEM was used to examine the morphological changes and quantitative element analysis to reveal the chemical composition of these phases in specimens. Various phase morphologies such as starlike, band shape and needlelike intermetallics were observed in these products, whereas the primary phase crystal structure is cubic and stable.