Synthesis of Fe–Al–Si intermediary phases by reactive sintering

Abstract

In this work, Fe–Al–Si alloys were prepared by reactive sintering. The contents of silicon and aluminium ranged between 0–30 wt‐% and 10–40 wt‐% respectively. Aluminium, silicon and AlSi30 master alloy powders prepared by mechanical machining and/or milling and commercial powder of high purity iron were used for sintering. Powders were blended and pressed at room temperature. Sintering was carried out at 950°C for 60 min. Compact low porosity products without unreacted components were prepared, if a powder mixture contained 15–20 wt‐% of silicon and 20–25 wt‐% of aluminium. It was shown that these materials contain two phases (Al₂FeSi and AlFeSi). Hardness of the alloys increased with growing silicon content, while the increase in aluminium content reduced the hardness.

Keywords:

• Iron aluminide
• Reactive sintering
• SHS
• Microstructure
• Hardness

The research of Fe–Al–Si intermetallics was financially supported by the research project no. KJB201250801 of the Grant Agency of the Academy of Sciences of the Czech Republic and by the research project of Ministry of Education, Youth and Sports of the Czech Republic (project no. MSM 6046137302).