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...

Fracture toughness is an important property that characterizes a material’s brittleness or resistance to fracture. Although some fracture toughness test methods have been refined and even standardized, many researchers have continued to use the Vickers indentation crack length method as an expedient. In this paper, Vickers indentation fracture resistance data for Standard Reference Material SRM...

The effects of silicon (Si) on the mechanical properties and fracture toughness of heavy-section ductile cast iron were investigated to develop material for spent-nuclear-fuel containers. Two castings with different Si contents of 1.78 wt.% and 2.74 wt.% were prepared. Four positions in the castings from the edge to the center, with different solidification cooling rates, were chosen for micros...

UNLABELLED The objective of this study was to investigate the correlation between filler size, fracture toughness and voids. Seven model resin composites and one commercial have been used in the study. A single edge notch mould was used to prepare samples (n=8). A selected area of 1mm below and above the notch was scanned with micro CT and then the percentage of voids calculated. A universal te...

statement  of  problem:  patients’ demand  for  tooth-colored  restoratives  in the posterior region is increasing. clinicians use universal nanohybrid resin composites for both anterior and posterior regions. there are few published reports comparing fracture toughness of nonohybrids and that of hybrid composite stored wet and dry. objectives: to investigate the fracture toughness of three nan...

The concrete community in the United States has reached the point where it needs a standard test for measuring the fracture toughness of concrete. A concrete standard might be obtainable by adapting existing standards for cemented carbides and rock. These standards use the short rod specimen geometry and two associated test methods. The combination of specimen geometry and test methods may have...

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...

Quantitative assessment of the strength and toughness of bone has become an integral part of many biological and bioengineering studies on the structural properties of bone and their degradation due to aging, disease and therapeutic treatment. Whereas the biomechanical techniques for characterizing bone strength are well documented, few studies have focused on the theory, methodology, and vario...

this article aims to review various modes of fracture toughness of resin composites. also, this study intends to review the papers on the fracture mode, namely “fractography”, under scanning electron microscopy finding fracture initiation site, and the effect of filler content on the fracture toughness of resin composites. it will also review the effect of aging on the fracture toughness of res...