Testing and characterization of ceramic thermal barrier coatings

Bartsch M., Baufeld B., DALKILIÇ S., Mircea I.

8th International Symposium on Multifunctional and Functionally Graded Materials, FGM2004, Leuven, Belçika, 11 - 14 Temmuz 2004, cilt.492-493, ss.3-8 identifier

  • Yayın Türü: Bildiri / Tam Metin Bildiri
  • Cilt numarası: 492-493
  • Doi Numarası: 10.4028/0-87849-970-9.3
  • Basıldığı Şehir: Leuven
  • Basıldığı Ülke: Belçika
  • Sayfa Sayıları: ss.3-8
  • Anahtar Kelimeler: Damage accumulation, Interfacial fracture toughness, Lifetime assessment, Realistic testing, Thermal barrier coatings, Thermal gradient, Thermal mechanical fatigue
  • Anadolu Üniversitesi Adresli: Evet

Özet

This paper gives a short overview of tests applied for the investigation of long term behaviour of thermal barrier coating systems. A variety of tests has been conducted on an exemplary material system with the coatings applied by electron beam physical vapour deposition. Damages and damage evolution in different tests are compared. Since the observed damage mechanisms are different, it is proposed to design laboratory tests as realistic as possible, especially if the test data are used for lifetime assessment. In order to get reasonable testing times, the damage accumulation has to be described as a function of loading history, long time before failure. For the case of final failure by spallation of the ceramic top coat, it is proposed to use the apparent interfacial fracture toughness as damage parameter, Several methods for measuring the apparent fracture toughness of brittle coatings are discussed with respect to their application to thermal barrier coating systems.