Characterize the microstructure, composition and some physical properties of a glass-infiltrated ... more Characterize the microstructure, composition and some physical properties of a glass-infiltrated alumina/zirconia-reinforced ceramic (IZ) and the effect of surface treatment on topography. IZ ceramic specimens were fabricated according to ISO6872 instructions and polished through 1 microm alumina abrasive. Quantitative and qualitative analyses were performed using scanning electron microscopy (SEM), backscattered imaging (BSI), electron dispersive spectroscopy (EDS) and stereology. The elastic modulus (E) and Poisson's ratio (nu) were determined using ultrasonic waves, and the density (rho) using a helium pycnometer. The following ceramic surface treatments were used: AP-as-polished; HF-etching with 9.5% hydrofluoric acid for 90 s; SB-sandblasting with 25 microm aluminum oxide particles for 15s and SC-blasting with 30 microm aluminum oxide particles modified by silica (silica coating) for 15s. An optical profilometer was used to examine the surface roughness (Ra) and SEM-EDS were used to measure the amount of silica after all treatments. The IZ mean property values were as follows: rho=4.45+/-0.01 g/cm(3); nu=0.26 and E=245 GPa. Mean Ra values were similar for AP- and HF-treated IZ but significantly increased after either SC or SB treatment (p<or=0.05). The surface concentration of Si(K) increased 76% after SC treatment. HF is an inadequate surface treatment for bonding resins to IZ ceramic. Treating IZ with either SB or SC produced greater Ra values and the SC showed a significant increase in the surface concentration of silica, which may enhance bonding to resin via silane coupling.
Half of a set of sapphire disks was exposed to fast neutrons (0.8-10 MeV) at a fluence of 10 neut... more Half of a set of sapphire disks was exposed to fast neutrons (0.8-10 MeV) at a fluence of 10 neutrons/m. Each 25-mm-diameter x 1-mm-thick disk was then exposed to a 10.6 μm CO laser (121 W/cm) while the central 12.7-mm-diameter region of the disk was shielded from ...
Page 1. The Effect of Stoichiometry on the Fracture Toughness of a Liquid Crystalline Epoxy ELIZA... more Page 1. The Effect of Stoichiometry on the Fracture Toughness of a Liquid Crystalline Epoxy ELIZABETH J. ROBINSON, ELLIOT P. DOUGLAS, and JOHN J. MECHOLSKY, JR. Department of Materials Science and Engineering University of Florida Gainesville, FL 3261 1-6400 ...
It is also possible that your web browser is not configured or not able to display style sheets. ... more It is also possible that your web browser is not configured or not able to display style sheets. In this case, although the visual presentation will be degraded, the site should continue to be functional. We recommend using the latest version of Microsoft or Mozilla web browser to ...
Fractal geometry is a non-Euclidean geometry which has been developed to analyze irregular or fra... more Fractal geometry is a non-Euclidean geometry which has been developed to analyze irregular or fractional shapes. In this paper, fracture in ceramic materials is analyzed as a fractal process. This means that fracture is viewed as a self-similar process. We have examined ...
Page 1. J. Am. Ceram. SOC., 72 [9] 1584-87 (1989) journal Use of Crack Branching Data for Measuri... more Page 1. J. Am. Ceram. SOC., 72 [9] 1584-87 (1989) journal Use of Crack Branching Data for Measuring Near-Surface Residual Stresses in Tempered Glass Joseph C. Conway, Jr.,* and John J. Mecholsky, Jr.*rt Department of ...
Fractal geometry has been used to describe irregular frac-ture surfaces in a quantitative way. Th... more Fractal geometry has been used to describe irregular frac-ture surfaces in a quantitative way. The fractal dimensional increment has been related to the fracture toughness of the material through the elastic modulus and a characteristic structure parameter, ao. The study of ...
Characterize the microstructure, composition and some physical properties of a glass-infiltrated ... more Characterize the microstructure, composition and some physical properties of a glass-infiltrated alumina/zirconia-reinforced ceramic (IZ) and the effect of surface treatment on topography. IZ ceramic specimens were fabricated according to ISO6872 instructions and polished through 1 microm alumina abrasive. Quantitative and qualitative analyses were performed using scanning electron microscopy (SEM), backscattered imaging (BSI), electron dispersive spectroscopy (EDS) and stereology. The elastic modulus (E) and Poisson's ratio (nu) were determined using ultrasonic waves, and the density (rho) using a helium pycnometer. The following ceramic surface treatments were used: AP-as-polished; HF-etching with 9.5% hydrofluoric acid for 90 s; SB-sandblasting with 25 microm aluminum oxide particles for 15s and SC-blasting with 30 microm aluminum oxide particles modified by silica (silica coating) for 15s. An optical profilometer was used to examine the surface roughness (Ra) and SEM-EDS were used to measure the amount of silica after all treatments. The IZ mean property values were as follows: rho=4.45+/-0.01 g/cm(3); nu=0.26 and E=245 GPa. Mean Ra values were similar for AP- and HF-treated IZ but significantly increased after either SC or SB treatment (p<or=0.05). The surface concentration of Si(K) increased 76% after SC treatment. HF is an inadequate surface treatment for bonding resins to IZ ceramic. Treating IZ with either SB or SC produced greater Ra values and the SC showed a significant increase in the surface concentration of silica, which may enhance bonding to resin via silane coupling.
Half of a set of sapphire disks was exposed to fast neutrons (0.8-10 MeV) at a fluence of 10 neut... more Half of a set of sapphire disks was exposed to fast neutrons (0.8-10 MeV) at a fluence of 10 neutrons/m. Each 25-mm-diameter x 1-mm-thick disk was then exposed to a 10.6 μm CO laser (121 W/cm) while the central 12.7-mm-diameter region of the disk was shielded from ...
Page 1. The Effect of Stoichiometry on the Fracture Toughness of a Liquid Crystalline Epoxy ELIZA... more Page 1. The Effect of Stoichiometry on the Fracture Toughness of a Liquid Crystalline Epoxy ELIZABETH J. ROBINSON, ELLIOT P. DOUGLAS, and JOHN J. MECHOLSKY, JR. Department of Materials Science and Engineering University of Florida Gainesville, FL 3261 1-6400 ...
It is also possible that your web browser is not configured or not able to display style sheets. ... more It is also possible that your web browser is not configured or not able to display style sheets. In this case, although the visual presentation will be degraded, the site should continue to be functional. We recommend using the latest version of Microsoft or Mozilla web browser to ...
Fractal geometry is a non-Euclidean geometry which has been developed to analyze irregular or fra... more Fractal geometry is a non-Euclidean geometry which has been developed to analyze irregular or fractional shapes. In this paper, fracture in ceramic materials is analyzed as a fractal process. This means that fracture is viewed as a self-similar process. We have examined ...
Page 1. J. Am. Ceram. SOC., 72 [9] 1584-87 (1989) journal Use of Crack Branching Data for Measuri... more Page 1. J. Am. Ceram. SOC., 72 [9] 1584-87 (1989) journal Use of Crack Branching Data for Measuring Near-Surface Residual Stresses in Tempered Glass Joseph C. Conway, Jr.,* and John J. Mecholsky, Jr.*rt Department of ...
Fractal geometry has been used to describe irregular frac-ture surfaces in a quantitative way. Th... more Fractal geometry has been used to describe irregular frac-ture surfaces in a quantitative way. The fractal dimensional increment has been related to the fracture toughness of the material through the elastic modulus and a characteristic structure parameter, ao. The study of ...
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