title: Full-field measurement of nonuniform stresses of thin films at high temperature.
abstract: Coherent gradient sensing (CGS), a shear interferometry method, is developed to measure the full-field curvatures of a film/substrate system at high temperature. We obtain the relationship between an interferogram phase and specimen topography, accounting for temperature effect. The self-interference of CGS combined with designed setup can reduce the air effect. The full-field phases can be extracted by fast Fourier transform. Both nonuniform thin-film stresses and interfacial stresses are obtained by the extended Stoney's formula. The evolution of thermo-stresses verifies the feasibility of the proposed interferometry method and implies the "nonlocal" effect featured by the experimental results.
authors: AML, Department of Engineering Mechanics, Tsinghua University, Beijing, China.
authors: Xuelin
authors: X
authors: Dong
authors: Xue
authors: X
authors: Feng
authors: Keh-Chih
authors: KC
authors: Hwang
authors: Shaopeng
authors: S
authors: Ma
authors: Qinwei
authors: Q
authors: Ma
mesh_terms: D055119:Elastic Modulus; D006358:Hot Temperature; D007368:Interferometry / Q000379:methods*; D008422:Materials Testing / Q000379:methods*; D008567:Membranes, Artificial; D013314:Stress, Mechanical
chemical_list: D008567:Membranes, Artificial