Fracture behaviour of Fe3Al and FeAl type iron aluminides

Fracture behaviour of two intermetallic alloys based on FeAl and Fe3Al was studied. On the alloys Fe-40Al-1C (at%) and Fe-29.5Al-2.3Cr-0.63Zr-0.2C (at%) (FA06Z), a basic characterization, the fracture toughness tests and fractographic analysis were carried out. Tensile tests and fracture toughness tests were performed at 20, 200, 400 and 600 degrees C. The fracture toughness values range from 26 MPa.m(1/2) at 20 degrees C to 42 MPa.m(1/2) at 400 degrees C. In addition, J-integral dependence on Act obtained by potential method was measured. The fractographic analysis showed that samples fractured at 20, 200 and 400 degrees C in the tensile or fracture toughness tests exhibit transgranular cleavage fracture, while at 600 degrees C the ductile dimple fracture predominates.