Finite element analysis of crack propagation and fracture mechanical properties of freestanding 8 wt.% Y2O3–ZrO2 coatings

• Fracture toughness and fracture strength of freestanding 8YSZ were measured by SENB.
• The fracture process was simulated by XFEM and energy release rate was estimated.
• The simulated fracture toughness is consistent well with that by SENB.

With the help of a digital image correlation technique, fracture strength and fracture toughness of freestanding 8 wt.% Y2O3–ZrO2 (8YSZ) coatings were directly measured by single edge notched bending (SENB) tests. An extended finite element model (XFEM) was established to simulate the fracture process of notched 8YSZ samples. Its energy release rate was estimated by the known fracture strength and Young's modulus. Within the linear elastic brittle fracture, the calculated energy release rate was transformed into the corresponding fracture toughness, which is in good agreement with the experimental results by SENB. The obtained material properties of XFEM in this work would play a crucial role in predicting the reliability and durability of TBCs with irregular geometry in the future.