statement of problem: tooth-coloured restorative materials are brittle with the major shortcomings of sensitivity to flaws and defects. although various mechanical properties of resin composites have been studied, no fracture toughness test data for nano-hybrid composites under acidic condition for a long period of time has been published. objectives: to compare the fracture toughness (k ic ) o...

The behaviour of some commercial tool carbides and turbine ceramics has been investigated in regard to resistance to crack initiation, crack propagation and retained strength after thermal shock. New data are provided, particularly measurements of the fracture toughness of these materials at actual operating temperatures (up to 1200 ~ C). Many of the materials did not follow the generally accep...

changes in moisture content and temperature can perturb both stiffness and strength and as such the impact resistance of composite structures. in this paper, the pre-notched basalt fibre reinforced epoxy (bfre) composite specimens are studied under charpy impact loads in order to investigate the changes in impact energy absorption (fracture toughness) with different kinds of aging conditions. t...

The proportional relationships between the Charpy absorbed energy (CVN) and the KIC values have been established for a wide variety of steels. Several formulae have been proposed that predict KIC from CVN. The purpose of this study is to investigate, by means of compact testing fracture toughness specimens, the effective role of microstructure for estimation of the fractur...

Introduction: The fracture mechanisms of bone tissue have been described as a damage accumulation process, which starts with the initiation and propagation of microcracks. Knowledge of crack initiation and propagation at tissue level (tissue fracture toughness) is critical to understand and prevent bone fractures. Tissue fracture toughness could provide valuable information for defining bone qu...

Biocompatible materials used for the fabrication of dental crowns were studied. Patients were treated with Gold, Porcelain and Zirconia crowns. Dental crowns were selected according to patient’s clinical status and needs. We found that Gold crowns had low patient acceptance because of poor aesthetics and high cost. Gold crowns could not be used opposite to amalgam restorations for the fear of g...

The mode II initiation fracture toughness of wood was measured by the three-point bend endnotched flexure (3ENF) test for various crack lengths, and the dependence of toughness on the crack length was analyzed by the four conventional methods of data reduction : elementary beam theory, Williams end correction method, and two compliance calibration methods. In addition to these methods, the comp...

The knowledge of load bearing characteristics and failure of material is very important for mechanical engineers. Various metallic, non metallic and composite materials are used in different application. In view of this, the main objective of the present work is to analyze the influence of Aluminum Oxide filler on Fracture Toughness properties of Chopped Strand Mat (CSM) E-Glass Fiber reinforce...

[1] Dry slab avalanches release by propagation of shear fractures in a thin, planar weak layer underneath a cohesive, stronger slab. This implies that a balance between shear fracture toughness and the shear fracture stress intensity factor fundamentally determines snow slab stability. Conventionally, fracture toughness is a material property and, for most materials, emphasis is on tensile frac...

In this investigation ‚the fracture toughness of A356 containing15%SiC composite was studied. Al/SiC composites have been considered because of their mechanical and erosion properties .Low fracture toughness in Al/SiC as compared with Aluminium alloys is one of its disadvantage. In this study at first A356 alloy was melted in a smelting electrical furnace then poured into the mould. A356-15% Si...