Determination of fracture toughness of zirconia ceramics with different yttria concentrations by SEVNB method

Comparison of fracture toughness measurements for zirconia materials using two test methods

“…The first mentioned observation of significantly higher K IC values for SEVNB aggregates to the concerns of overestimated values found in literature 13,16) , which are attributed to the method itself: SEVNB leads to higher K IC when fine-grained Y2O3 stabilized zirconia is investigated because of the notch root radius sizes, which exceed the magnitude of the microstructure. Several investigations and a round robin have highlighted this limitation 10,13,15,17) . To the current state, even adaptation factors to the theoretical fracture toughness, like 1.5 16) , have been examined.…”

“…The single-edge-V-notch-beam (SEVNB) method, which is well-established, widely used and easy to implement, leads to a high scattering of the measured values 13) and is considered unsuitable for fine-grained materials with a grain size smaller than 1 µm 14) , as the so-called "notch root radius effect" and an overestimation of the K IC occurs [15][16][17] . With regard to the sharpness of the SEVNB notch root radius, the notches produced with razor blades are significantly limited by the razor blade geometry (approx.…”

“…With regard to the sharpness of the SEVNB notch root radius, the notches produced with razor blades are significantly limited by the razor blade geometry (approx. 18 17) or 10 µm 10) ) and for the Y2O3 stabilized zirconia with grain sizes of 437 nm (3 mol% Y2O3) or 858 nm (5 mol% Y2O3) insufficiently thin 17) . Instead of an initial crack, the CNB process is based on a triangle cross-section where the crack proceeds from one tip through the material with an increasing geometry factor until it fractures 7,18) .…”

Load‐deflection behavior of fracture toughness testing of ceramics by SEVNB method

“…In our previous work, the load‐deflection curves of 3Y‐TZP ceramic measured by SEVNB method testing revealed that the cracks experienced a growth stage which is different from the direct fracture of SENB method. However, few studies have been reported to investigate the load‐deflection curve of fracture toughness testing by the modified SEVNB method.…”

Dry‐sliding wear behavior of 3Y‐TZP/Al2O3‐NbC nanocomposites produced by conventional sintering and spark plasma sintering

“…Structural ceramics combining high mechanical properties are an interesting choice for engineering applications. 3Y‐TZP is such a material, exhibiting the highest fracture toughness among monolithic structural ceramics . However, 3Y‐TZP has a moderate hardness compared to other structural ceramics, such as alumina and cermets .…”