Novel high-entropy (multi-principal elements) alloy based on Fe-Al-Si-Ni-Ti in equimolar proportions has been developed. The alloy powder obtained by mechanical alloying is composed of orthorhombic FeTiSi phase with the admixture of B2 FeAl. During spark plasma sintering of this powder, the FeSi phase is formed and the amount of FeAl phase increases at the expense of the FeTiSi phase. The material is characterized by a high compressive strength (approx. 1500 MPa) at room temperature, being brittle. At 800 °C, the alloy is plastically deformable, having a yield strength of 459 MPa. The wear resistance of the material is very good, comparable to the tool steel. During the wear test, the spallation of the FeSi particles from the wear track was observed locally.

• Keywords
• aluminide, high-entropy alloy, silicide,
• Publication type
• Journal Article MeSH

The effect of phase composition and morphology on high-temperature strength in the compression of Fe-Al-Si-based iron aluminides manufactured by casting was investigated. The structure and high-temperature strength in the compression of three alloys-Fe28Al5Si, Fe28Al5Si2Mo, and Fe28Al5Si2Ti-were studied. Long-term (at 800 °C for 100 h) annealing was performed for the achievement of structural stability. The phase composition and grain size of alloys were primarily described by means of scanning electron microscopy equipped with energy dispersive analysis and Electron Backscatter Diffraction (EBSD). The phase composition was verified by X-ray diffraction (XRD) analysis. The effect of Mo and Ti addition as well as the effect of long-term annealing on high-temperature yield stress in compression were investigated. Both additives-Mo and Ti-affected the yield stress values positively. Long-term annealing of Fe28Al5Si-X iron aluminide alloyed with Mo and Ti deteriorates yield stress values slightly due to grain coarsening.

• Keywords
• Fe-Al-Si cast alloys, Ti and Mo alloying, high-temperature strength in compression, long-term annealing, microstructure,
• MeSH
• Aluminum chemistry   MeSH
• Silicon chemistry   MeSH
• Mechanical Phenomena MeSH
• Microscopy, Electron, Scanning MeSH
• Molybdenum chemistry   MeSH
• Alloys chemistry   MeSH
• Materials Testing MeSH
• Titanium chemistry   MeSH
• Hot Temperature MeSH
• Iron chemistry   MeSH
• Phase Transition MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Aluminum MeSH
• Silicon MeSH
• Molybdenum MeSH
• Alloys MeSH
• Titanium MeSH
• Iron MeSH