Assessment of variations in thermal cycle life data of thermal barrier coated rods
Abstract
An analysis of thermal cycle life data for 22 thermal barrier coated (TBC) specimens was conducted. The Zr028Y203/NiCrAlY plasma spray coated Rene 41 rods were tested in a Mach 0.3 Jet A/air burner flame. All specimens were subjected to the same coating and subsequent test procedures in an effort to control three parametric groups; material properties, geometry and heat flux. Statistically, the data sample space had a mean of 1330 cycles with a standard deviation of 520 cycles. The data were described by normal or lognormal distributions, but other models could also apply; the sample size must be increased to clearly delineate a statistical failure model. The statistical methods were also applied to adhesive/cohesive strength data for 20 TBC discs of the same composition, with similar results. The sample space had a mean of 9 MPa with a standard deviation of 4.2 MPa.
 Publication:

Presented at the Intern. Conf. on Met. Coatings
 Pub Date:
 1981
 Bibcode:
 1981meco.confR...6H
 Keywords:

 Fatigue Life;
 Temperature Effects;
 Thermal Stresses;
 Thermodynamic Cycles;
 Failure Analysis;
 Oxidation;
 Protective Coatings;
 Reaction Kinetics;
 Fluid Mechanics and Heat Transfer