Refinement of Fe 4 Al 13 in Al–Fe alloys by plasma remelting process

Abstract

Refinement of the Fe₄Al₁₃ phase in Al–Fe (wt-%) alloys has been achieved by a plasma remelting process. The refinement effect is enhanced by increases of discharge current and argon flux. The average size of the Fe₄Al₁₃ is 40 µm in Al–1Fe alloy melted using an electric resistance furnace. This can be reduced to 0.4 µm by a plasma remelting process. Similarly, the average size of the Fe₄Al₁₃ in Al–5Fe alloy can be decreased from 60 to 3 µm by plasma remelting. The refinement is considered to be an effect of the decrease of cluster size retaining genetic information in the Al–Fe alloy melt, the homogenisation of microstructure in the melt, and the increased undercooling during solidification.