Mechanical alloying and vacuum sintering have been used to produce bulk nanostructured Ti5Si3 and Ti5Si3-15Wt.% Al2O3 nanocomposite. X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) were used to study the microstructural characteristics of the samples. Indentation method was used to calculate hardness, elastic modulus and fracture toughness ...

EFFECTS OF RUBBER ADDITIVES ON PROPERTIES OF ASPHALTIC MATERIALS by JOHN ALBERT ALEXANDER Submitted to the Department of Civil Engineering on August 17, 1968, in partial fulfillment of the requirements for the degree of Master of Science in Civil Engineering. This study investigated the modification of asphalt with various rubbers and the effect of this modification on the values of fracture to...

Failures in composite materials occur mainly due to interlaminar fracture, also called delamination, between laminates. This indicates that characterizing interlaminar fracture toughness is the most effective factor in the fracture of composite materials. This study reports investigation on mixed-mode interlaminar fracture behaviour in woven carbon fibre/polyetherimide (CF/PEI) thermoplastic co...

Results of experimental investigation carried out to study the effects of addition of natural san fibres on the fracture toughness and impact strength of high-volume fly ash concrete are presented in this paper. San fibres belong to the category of ‘Natural Bast Fibres’, also known as ‘Sunn Hemp’. Its scientific (botanical) name is Crotalaria Juncea. It is mostly grown in the Indian Sub-Contine...

Recently, a method for evaluating the fracture toughness of ceramics has been proposed by Fett based on the computed crack-opening displacements of cracks emanating from Vickers hardness indentations. To verify this method, experiments have been conducted to determine the toughness of a commercial silicon carbide ceramic, Hexoloy SA, by measuring the crack-opening profiles of such Vickers inden...

Fracture toughness tests were conducted for an A533B-1 steel by using chevron-notched compact specimens in the temperature range from the lower shelf regime up to the transition temperature in order to assess the R-curve for cleavage fracture. The applicability of these specimens to the simple fracture toughness test without introducing fatigue pre-cracks was examind. The following are the summ...

The effects of grain-boundary chemistry on the mechanical properties of a high-purity silicon nitride ceramics were investigated, with specific emphasis on the role of oxygen. Variations in the grain-boundary oxygen content, through control of oxidizing heat treatments and sintering additives, was found to result in a transition in fracture mechanism from transgranular to intergranular fracture...

The marginal fracture toughness of several types of composite resins was determined by means of the rattler test. Microparticle-filled resins showed significantly higher marginal fracture toughness than conventional composites. Posterior restorative composites were intermediate between MFRs and conventional composites. Amalgams were inferior to restorative resins. These data correspond with the...

The fracture toughness, K IC, of a cortical bone has been experimentally determined by several researchers. The variation of K IC values occurs from the variation of specimen orientation, shape, and size during the experiment. The fracture toughness of a cortical bone is governed by the severest flaw and, hence, may be analyzed using Weibull statistics. To the best of the authors' knowledge, ho...

. 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...