an epoxy resin was modified by silica nanoparticles and cured with an anhydride. the particles with different batches of 12, 20, and 40 nm sizes were each distributed into the epoxy resin ultrasonically. electron microscopy images showed that the silica particles were well dispersed throughout the resin. tensile test results showed that young’s modulus and tensile strength increased with the vo...

We found direct evidence that a single-crystal-like aragonite platelet is essentially assembled with aragonite nanoparticles. The aragonite nanoparticles are readily oriented and assembled into pseudo-single-crystal aragonite platelets via screw dislocation and amorphous aggregation, which are two dominant mediating mechanisms between nanoparticles during biomineralization. The heat treatment b...

The phase relations in the system S i A I Z r / N O are studied by experiment and by thermodynamic calculations. The resu Its show the conditions under which such ceramics can exist and thereby explain contradictions between earlier results. The knowledge of these phase equilibria makes it possible to choose suitable material compositions in order to apply the toughening effects of ZrO2 on a Si...

The possibility of using the "Brazilian test" method to determination tensile strength sigma t composite zirconia ceramics small-size samples were demonstrated and reliability obtained values confirmed. It was found that dependence alumina toughened (stabilized by calcium oxide) with silica addition (CaO-ATZ + SiO 2 ceramics) on concentration in them has a maximum (sigma_t=450...

Zirconia is a “metastable” ceramic, consisting of monoclinic, tetragonal, and cubic phases. Partially stabilized zirconia preferred choice for dental use since they offer the opportunity to fabricate prosthesis which not available with other ceramic materials. Phase transformation in ceramics represents one most remarkable innovations field. This phase can have desirable consequences, increase ...

A ceramic material suitable for packaging of large scale integrated circuit is produced by the process of forming a mixture of a powdered glass ceramic material which is a glassy precursor to cordierite ceramic material, formed by the steps which are as follows: a. Mix tetragonal phase material selected from the group consisting of zirconia or hafnia powder con taining a stabilizing oxide compo...

A numerical study on toughening laminated composite materials against delamination by initiating multiple interlaminar cracks is presented. Different configurations of interface and weakening patches, that modify the properties at selected locations, are investigated as a way to trigger delaminations. Both patches can be configured toughen material The initiation delaminations increase in tough...

Fracture and fatigue properties are examined for a series of Mo–Mo3Si–Mo5SiB2 alloys, which utilize a continuous a-Mo matrix to achieve unprecedented room-temperature fracture resistance (>20 MPa p m). Mechanistically, these properties are explained in terms of toughening by crack trapping and crack bridging by the more ductile a-Mo phase. 2003 Acta Materialia Inc. Published by Elsevier Ltd. Al...

The tough bulk of dentin in teeth supports enamel, creating cutting and grinding biostructures with superior failure resistance that is not fully understood. Synchrotron-based diffraction methods, utilizing micro- and nanofocused X-ray beams, reveal that the nm-sized mineral particles aligned with collagen are precompressed and that the residual strains vanish upon mild annealing. We show the l...