Abbreviated Journal Title
Appl. Phys. Lett.
BARRIER COATINGS; THERMOMECHANICAL FATIGUE; DAMAGE EVOLUTION; TBC; SYSTEM; SUPERALLOY; FAILURE; CRACKS; STRAINS; ALUMINA; CREEP; Physics, Applied
Experimental in situ synchrotron x-ray diffraction results tracking the strain behavior of the various layers during a cycle, under thermo-mechanical conditions are presented in this work. The quantitative strain measurements here show that the thermally grown oxide briefly experiences in-plane tensile stress (sigma(22) = +36.4 MPa) with increased mechanical loading during ramp-up in the thermal cycle. These findings are the first in situ experimental observations of these strains under thermo-mechanical conditions, envisaged to serve as a catalyst for crack initiation. The depth resolved measurements of strain taken during applied thermal and mechanical load in this work are a significant step towards achieving realistic testing conditions.
Applied Physics Letters
Diaz, Rene; Jansz, Melan; Mossaddad, Mitra; Raghavan, Seetha; Okasinski, John; Almer, Jonathan; Pelaez-Perez, Hugo; and Imbrie, Peter, "Role of mechanical loads in inducing in-cycle tensile stress in thermally grown oxide" (2012). Faculty Bibliography 2010s. 2489.