A fractographic study on tensile fracture surface of duplex microstructure TiAl alloy

The role of mechanical twinning on microcrack nucleation and crack propagation in a near-γ TiAl alloy

“…Lamellar microstructures (consisting of layers of the D0 19 a 2 phase and six orientation variants of the L1 0 g phase) typically have higher toughness and lower ductility compared to duplex alloys (consisting of equiaxed g and lamellar grains). Toughness is associated with the ability to resist and/ or arrest crack growth, and in TiAl, cleavage on {111} planes is facile [10]. Understanding how and why cracks propagate and arrest in these alloys can provide useful information for making strategic improvements in processing to improve the ductility and toughness.…”

Fracture initiation/propagation parameters for duplex TiAl grain boundaries based on twinning, slip, crystal orientation, and boundary misorientation

“…Though TiAl is highly appealing [1][2][3] for aerospace and automotive heat engine applications that require low density materials with high temperature strength, ambient-temperature toughness, and good corrosion resistance, the variability in the rather low ductility of TiAl has slowed its introduction into heat engines [4][5][6][7][8][9][10]. The high variability in ductility arises from the fact that there are a limited number of facile slip systems.…”