Mechanical features optimization for oxide films growing on alloy

Determination of Stress Fields and Identification of Thermomechanical Parameters in a Thermally Grown Oxide under Thermal Cycling Loadings, Using Advanced Models

“…1 and 5 to 10, has been performed with a Runge-Kutta numerical explicit scheme programmed in Matlab© language. Details on numerical aspects can be found in [10]. The geometry is a onedimensional one.…”

“…(14) If we consider the results found in [10], the authors suggest that the temperature dependence adapted to the present material may be:…”

“…This expression can be found in [1] and its validity has been verified in [10] in the range of temperature [700°C-900°C]. By considering either one of the mechanism or the other (but not the mixed case) and if grain size and diffusion coefficient follow an Arrhenius model, we suggest the following expression, noted as model J1 (where effect of the microstructure is present in the exponential function):…”

“…As a consequence, it is difficult to predict a general model with a universal dependence of the parameters with temperature. It is then always possible to consider the experimental results (for example those obtain in [10]) and try to fit with the best mathematical function. After some trials, the best fitting for Norton coefficient seems to be a power law, noted as model J2:…”

Determination of Residual Stress Fields in a Thermally Grown Oxide under Thermal Cycling Loadings, Using XRD and Raman Spectroscopy — Correlations with Microstructural States

“…In addition, stress release may also proceed by creep which should be less detrimental for the system. This behaviour has been suggested by [2,11] from growth stress evolution measurements in Ni30Cr alloys. In order to increase the durability of chromia forming alloys, it is mandatory to better understand such stress build up and relaxation mechanisms.…”