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

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.