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The effect of local deformation on the fracture behaviour of TiAl alloys was investigated.

Roller indentations impressed parallel to the crack plane significantly improve the

fracture toughness. The residual strains present in the indentation zone were characterized

by X-ray diffraction and modelled using finite element (FE) calculations. The experimentally

observed macrostrains exhibit remarkable crystallographic anisotropies and are unequally

shared between the major alloy constituents. The mechanisms behind the observed toughening

have been discussed in terms of the residual strains and factors improving the crack tip

plasticity. With regard to intended high-temperature applications, the temperature

retention of the toughening effect was studied.
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