Effect of Mn on Fe phases in spray-deposited Al-25Si-xFe-yMn alloys

Al-25Si-xFe-yMn alloys with the mass ratio of Mn to Fe between 0 and 1 were synthesized by spray deposition.The microstructure of the spray-deposited preforms was investigated by SEM,XRD and EDX.The results indicated that Mn addition could improve the morphology of Fe phases through forming particulate α-Al₁₅ (Fe,Mn)₃Si₂ phase to replace acicular δ-Al₄FeSi₂ and β-Al₅FeSi phases.When the mass ratio of Mn to Fe increased,the amount of particulate α-Al₁₅ (Fe,Mn)₃Si₂ phase would increase,whereas the amount of acicular phases reduced.When the mass ratio of Mn to Fe increased to 0.83 or 1,only particulate α-Al₁₅ (Fe,Mn)₃Si₂ phase could be observed in the deposited preform.