Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
857080 | Procedia Engineering | 2015 | 5 Pages |
Thermal barrier coatings are widely used in section of turbine engines. The effect of a transient thermal load on a coating which is bonded to a square substrate is analyzed using FEM method. Coatings are assumed to contain embedded cracks and they are thermally loaded according toa transientlow temperature environment. Thermal barrier coatingmixed I/II mode fracture criterion was established, Our models take into account various locations of cracks, crack delamination instances including different crack positions between ceramic coating and bond coating were analyzed. It's found that under thermal shockthe crack tip fields are shear-dominant. The total energy release rate and the stress intensity factor of mode IIof interfacial crack is greater than that of ceramic coating, indicating that once the unilateral interfacial crackappears, the unstable propagation of interfacial crackis more likely tooccur subsequently.