Mechanical twinning in Ni-based single crystal superalloys during multiaxial creep at 1050 °C

Jean-Briac Le Graverend (1) , Florence Pettinari-Sturmel (2) , Jonathan Cormier (1) , Muriel Hantcherli (2) , Patrick Villechaise (1) , Joël Douin (2)

1 ENDO - ENDOmmagement et durabilité [Institut Pprime]
2 CEMES-PPM - Physique de la Plasticité et Métallurgie

Multiaxial high-temperature creep tests have been performed at 1050 °C on a first-generation Ni-based single-crystal superalloy through the use of asymmetric notched specimens. Mechanical twins have been observed by EBSD and TEM analyses. A finite element simulation in a crystal plasticity framework has also been carried out to better understand the presence of mechanical twins at stress concentrators depending on stress triaxiality, plastic strain rate, and damage level.

Mots clés: High temperature; Creep; Deformation mechanism; Mechanical twinning; Nickel base single crystal superalloy

Domaines: Science des matériaux [cond-mat.mtrl-sci]; Mécanique des matériaux [physics.class-ph]; Matériaux

Jean-Briac Le Graverend, Florence Pettinari-Sturmel, Jonathan Cormier, Muriel Hantcherli, Patrick Villechaise, et al.. Mechanical twinning in Ni-based single crystal superalloys during multiaxial creep at 1050 °C. Materials Science and Engineering: A, 2018, 722, pp.76-87. ⟨10.1016/j.msea.2018.02.086⟩. ⟨hal-02062064⟩