Effect of C, Ti, Zr and B alloying on fracture mechanisms in hot-rolled Fe-40 (at.%)Al

This paper reports a study of fracture behavior of FeAl-based intermetallic alloys with the addition of carbon, titanium, zirconium and boron (Fe-40Al-1C, Fe-40Al-1Ti and Fe-40Al-Zr-B). The alloys were prepared by modified processing technology of vacuum induction melting and hot rolling in special stainless steel sheath. Tensile and fracture toughness tests were carried out at 20 °C, 400 °C, 600 °C, 700 °C and 800 °C. The alloy showed best fracture toughness and tensile properties with Zr and B addition. The fracture toughness at 600 °C was comparable with values in stainless steels and nickel-based superalloys. The fractographic analysis revealed the change of fracture micromechanisms with temperature. Moreover, under specific conditions, the fracture micromechanisms were different in tensile and fracture toughness specimens.