Mechanisms for Interfacial Toughness Loss in Thermal Barrier Coating Systems

The Effects of Oxidation-Induced Failures on Thermal Barrier Coatings with Platinum Aluminide and NiCoCrAlY Bond Coats

“…These defects consisted of, areas where the TBC was detached from the TGO and bond coat, Figure 18, areas where cracks initiated at locations where transient oxides had formed in the TGO, Figure 19, oxide protrusions that extended into the bond coat due to reactive element oxidation, Figure 17c, and oxide inclusions that were in the as-processed bond coats. To examine the fracture path of the TBCs as a function of exposure time, an indent test (12) was used to cause failure of the TBC at times shorter than that caused by cyclic oxidation. The results obtained from this test are presented in Figure 20.…”

On cracks and delaminations of thermal barrier coatings due to indentation testing: Experimental investigations

“…9 (dashed lines). This implies that that the interfacial tough ness increases as the system ages and is at variance to the common understanding of the evolution of material prop erties of TBCs [8,23,24]. Moreover, it appears as the response can be divided into two cases: ''small" and ''large" maximum indentation force.…”

Fundamental Studies of the Durability of Materials for Interconnects in Solid Oxide Fuel Cells

“…The use of indentation as a means for inducing chromia scale spallation from interconnect alloys builds upon previous research by the PIs involving indentation of thermal barrier coating (TBC) systems [26,27]. Testing goals in TBC and interconnect alloy systems are similar, where an understanding of mechanisms leading to coating spallation is needed, as are methods for accelerating cyclic thermal testing to evaluate new coating/substrate systems.…”