Abstract
This study investigates the influence of segmentation crack density on the strain tolerance of thermal barrier coatings produced by atmospheric plasma spraying. A Triplex II plasma gun is used to spray fused and crushed yttria-stabilized zirconia, forming thick deposits with high segmentation crack densities, low porosity, and low branching crack density, which is necessary for good interlamellar bonding. Thermal cycling and burner rig tests yield promising results in terms of lifetime and strain tolerance behavior and microstructural analysis shows that the segmentation crack network was stable during thermal shock testing. The main failure mechanism was delamination and horizontal cracking in the vicinity of the TBC-TGO (thermally grown oxide) interface.
