Mechanical behavior of freestanding 8YSZ thin films under tensile and bending loads

Bioinspired High Tolerant Vein–Membrane Al2O3 Coating

“…This is 2 orders of magnitude higher than the reported failure strain of Al 2 O 3 film (0.07%) and comparable to the bioinspired nacre‐like composites (<5%). [ 56–58 ] It is also an order of magnitude higher than the strain‐tolerant ceramic coatings, such as YSZ (catastrophic cracks under 0.1%–0.2% strain) [ 17,59–61 ] and Al 2 O 3 ‐ZrO 2 (fatal cracks under 0.2% strain). [ 18 ] The vein–membrane coating only contains Al 2 O 3 , which is different from multi‐component bioinspired nacre‐like Al 2 O 3 and composite ceramic coatings.…”

“…(<5%). [56][57][58] It is also an order of magnitude higher than the strain-tolerant ceramic coatings, such as YSZ (catastrophic cracks under 0.1%-0.2% strain) [17,[59][60][61] and Al 2 O 3 -ZrO 2 (fatal cracks under 0.2% strain). [18] The vein-membrane coating only contains Al 2 O 3 , which is different from multi-component bioinspired nacre-like Al 2 O 3 and composite ceramic coatings.…”

A Review on In Situ Mechanical Testing of Coatings

“…The in situ DIC measurements allowed us to directly observe dynamic strain fields, surface cracks' initiation, and propagation as well as predict the mechanical properties of TBCs (e.g., interface shear strengths, fracture strengths, fracture toughness, and fracture energy). Patibanda et al [69] investigated the real-time tensile and bending characteristics of plasma-sprayed, freestanding TBCs. The strain distribution over the deformed samples was recorded during the testing process using DIC.…”

“…The coatings that show high resistance to cracking exhibited high fracture toughness values and better adhesion to the substrate material under thermomechanical loading. The bending-driven fracture is considered to be an efficient technique to examine the durability of coatings at different temperatures [69,76,77], cracking behaviors [69,78,79], thicknesses [80], and deposition method effects [18].…”

“…The in situ bending experimentation allowed us to characterize the crack propagation at different BC topographies, and it showed that BC topographical features affect the crack propagation path and velocity. Patibanda et al [69] utilized in situ four-point bending experimentation to explore the failure behavior of TBC samples under varied stress states and determine the mechanical properties of TBC under bending conditions such as flexure strength and bending modulus. It was found that the values of bending strength and modulus were higher than those obtained from uniaxial tension trials.…”