M. Werwer et A. Cornec, Numerical simulation of plastic deformation and fracture in polysynthetically twinned (PST) crystals of TiAl, COMP MAT SC, 19(1-4), 2000, pp. 97-107
Plastic deformation and fracture in polysynthetically twinned (PST) crystal
s of TiAl have been simulated by using periodic unit cells representing the
relaxed-constraint model recently proposed by Lebensohn et al. [Acta Mater
. 46 (1998) 4701-4709] for the co-deformation of the lamellar compound of P
ST-TiAl. The unit cells contain both intermetallic phases, alpha (2)-(Ti3Al
) and gamma-(TiAl). Furthermore, the six orientation variants of the gamma
-phase are also considered. The constitutive behaviour of both phases is de
scribed by crystal plasticity, and the damage behaviour has been implemente
d by means of cohesive elements. The unit cells have been used as submodels
for multi-scale finite element simulations of compression tests acid fract
ure mechanics tests of notched micro-bend specimens. It is shown that the a
nisotropy of plastic deformation and damage in PST-TiAl can be well represe
nted. (C) 2000 Elsevier Science B.V. All rights reserved.