Fractographic and microstructural study of isothermally and cyclically heat treated thermal barrier coatings
2014 (English)In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 243, 82-90 p.Article in journal (Refereed) Published
The fracture surfaces from adhesion tested thermal barrier coatings (TBC) have been studied by scanning electron microscopy. The adhesion test have been made using the standard method described in ASTM 633, which makes use of a tensile test machine to measure the adhesion. The studied specimens consist of air plasma sprayed (APS) TBC deposited on disc-shaped substrates of Hastelloy X. The bond coat (BC) is of NiCoCrAlY type and the top coat (TC) consists of yttria–stabilised–zirconia. Before the adhesion test, the specimens were subjected to three different heat treatments: 1) isothermal oxidation 2) thermal cycling fatigue (TCF) and 3) burner rig test (BRT). The fracture surfaces of the adhesion tested specimens where characterised. A difference in fracture mechanism were found for the different heat treatments. Isothermal oxidation gave fracture mainly in the top coat while the two cyclic heat treatments gave increasing amount of BC/TC interface fracture with number of cycles. Some differences could also be seen between the specimens subjected to burner rig test and furnace cycling.
Place, publisher, year, edition, pages
2014. Vol. 243, 82-90 p.
Thermal barrier coating, TBC, fractography, adhesion, thermal cycling, burner rig
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-67883DOI: 10.1016/j.surfcoat.2012.02.040ISI: 000335542100014OAI: oai:DiVA.org:liu-67883DiVA: diva2:414006
On the day of the defence date of the Thesis the status of this article was Manuscript.2011-05-022011-05-022014-06-05Bibliographically approved