Electric tields can mtluence the fracture toughness offerroelectrics. For example, poled ferroelectrrcs cxhtbit fracture toughness anisotropy : the material is tougher for a crack parallel to the poling direction but less tough for a crack perpendicular to it. When an electric field is applied to a poled sample. a positive field reduces its fracture toughness but a negative field enhances it. P...

Indentation techniques for assessing fracture toughness are attractive due to the simplicity and expediency of experiments, and because they potentially allow the characterization of both local and bulk fracture properties. Unfortunately, rarely have such techniques been proven to give accurate fracture toughness values. This is a concern, as such techniques are seeing increasing usage in the s...

Mechanical behaviour of unsaturated polyester resin used for the composite materials has been studied to determine various important parameters, such as tensile and compressive, single edge-notch tensile fracture toughness, flexural properties and fracture energy. Fracture toughness, KIC, and fracture energy, GIC, obtained for the polyester resin lie between the typical values for epoxy resins ...

An investigation into the mixed mode fracture of steel fiber reinforced concrete (SFRC)beams with one percent volume fraction of steel fiber is presented. A series of notched beams withdifferent notch depths and locations are tested under three-point bending. The test results for apparentfracture toughness, crack trajectories, and fracture energy are presented. The crack paths for SFRCand plain...

A new approach to defining the effective fracture toughness for heterogeneous materials is proposed. This temporal averaging process dependent, incorporating crack velocity and material toughness. The effectiveness of technique investigated in context hydraulic through rock with a periodic plane strain model considered without fluid leak-off, more easily investigate different regimes (toughness...

Oxide Dispersion Strengthened (ODS) and TZM molybdenum have excellent creep resistance and strength at high temperatures in inert atmospheres. Fracture toughness and tensile testing was performed at temperatures between -1 50°C and 450°C to characterize 6.35 mm thick plate material of ODS and TZM molybdenum. A transition from low fracture toughness values (5.8 to 29.6 MPaJm) to values > 30 MPaJ...

Microencapsulated dicyclopentadiene (DCPD) healing agent and Grubbs’ Ru catalyst are incorporated into an epoxy matrix to produce a polymer composite capable of self-healing. The fracture toughness and healing efficiency of this composite are measured using a tapered double-cantilever beam (TDCB) specimen. Both the virgin and healed fracture toughness depend strongly on the size and concentrati...

Various types of hydroxyapatite (HA) structures have received great attention of scientific researcher in biomaterials field. Also, it is common that HA is the essential inorganic materials in human hard tissue such as bone or teeth. Fracture toughness and micro-hardness properties are the important parameters required for the prediction of the mechanical performance of biomaterials structures ...

The dynamic response mechanism of the rock fragmentation and its influential factors by TBM disc cutter are studied in this paper. Firstly, a dynamic response model is established based on the fracture mechanics and finite element theory. Secondly, a fragmentation rule is founded according to the dynamic response model, and then numerical simulations for dynamic response of rock are carried out...

The effect of microstructural variations on the fracture toughness of Alloy 718 was reviewed. The metallurgical parameters surveyed in this paper included heat treatment, heat-to-heat variations, product-form variations, neutron irradiation and long-term thermal aging. Key microstructural features and operative fracture mechanisms were related to macroscopic fracture toughness properties.