Thermomechanical fatigue behavior of an air plasma sprayed thermal barrier coating system

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Structural materials : properties, microstructure and processing, 2011, Vol.528 (29), p.8396-8401
• Main Authors: Chen, Z.B., Wang, Z.G., Zhu, S.J.
• Format: Article
• Language: English
• Subjects: Air plasma; Air plasma spraying; Applied sciences; Coating; Exact sciences and technology; Fatigue; Fatigue (materials); Fatigue failure; IP (Internet Protocol); Materials science; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metals. Metallurgy; Spallation; Strain; Thermal barrier coating; Thermal barrier coatings; Thermomechanical fatigue
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2011.08.031

► Lamp furnace is developed to heat for TBC system in thermomechanical fatigue tests. ► Phase conditions influence the stress distribution of the coating. ► Stress distribution decides the lifetime and fracture behavior of the coating. Failure behavior of an air plasma sprayed thermal barrier coating (TBC) system was investigated under in-phase (IP) and out-of-phase (OP) thermomechanical fatigue (TMF) tests. All the TMF tests were performed in the temperature range of 450–850 °C with a given period of 300 s under mechanical strain control. Both the bond coat NiCrAlY and the top coat 7%Y 2O 3–ZrO 2 were fabricated by air plasma spraying (APS). Results revealed that the IP TMF lifetime was longer than that of the OP TMF under the same mechanical strain amplitude. Morphology observations of the failed specimens showed that the coating cracking and spallation processes were different in the two phase conditions.