Correlating fracture toughness and fracture surface roughness via correlation length scale

ImpaCT Of SURfaCe ROUghNeSS ON flexURal STReNgTh aND fRaCTURe TOUghNeSS Of IN-CeRam ZIRCONIa

. AbstrAct Objective. In clinical practice, core material can be exposed after adjustments, which may result in loss of ceramic glaze. The objective of this study is to evaluate the effect of surface roughness on the flexural strength and fracture toughness of In-Ceram zirconia core material. Materials and methods. Forty In-Ceram zirconia specimens were prepared and divided into two main groups...

Fracture toughness of graphene.

Perfect graphene is believed to be the strongest material. However, the useful strength of large-area graphene with engineering relevance is usually determined by its fracture toughness, rather than the intrinsic strength that governs a uniform breaking of atomic bonds in perfect graphene. To date, the fracture toughness of graphene has not been measured. Here we report an in situ tensile testi...

Correlation between fracture surface morphology and toughness in Zr-based bulk metallic glasses

Fracture surfaces of Zr-based bulk metallic glasses of various compositions tested in the as-cast and annealed conditions were analyzed using scanning electron microscopy. The tougher samples have shown highly jagged patterns at the beginning stage of crack propagation, and the length and roughness of this jagged pattern correlate well with the measured fracture toughness values. These jagged p...

Fracture Toughness of Metal Castings

Roughness of fracture surfaces

We study the fracture surface of three dimensional samples through a model for quasi-static fractures known as Born Model. In particular, we consider the roughness of this fracture surface. We find for the roughness exponent a value ζ = 0.5 expected for “small length scales” in microfracturing experiments. Since this corresponds to a slow evolution for the fracture, our simulations confirm that...