摘要:

Raman spectroscopy was used to characterize phase transformations and transition temperatures in partially stabilized zirconia containing ≤20 wt% Y2O3. The completeness of the martensitic transition and its thermal hysteresis was followed in samples with ≤4 wt% Y2O3. Between 5 and 12 wt% the spectra indicate a tetragonal modification precipitated in a disordered cubic fluorite matrix. Above 15 wt% a “density of states” spectrum prevails that is characteristic of the fully stabilized disordered cubi

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1985.tb10176.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Techniques for preparation and the properties of phosphorus oxynitride glasses produced from sodium metaphosphate and nitride compounds are reported. Properties reported include nitrogen content, dissolution rate in water, thermal expansion coefficient, softening point, glass transformation temperature, density, refractive index, microhardness, and infrared absorption.

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1985.tb10177.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Barium oxide and carbon were added to β‐Sic powder as sintering aids. When only BaO or C was added, the Sic powder did not densify. However, densification was promoted by adding both additives together. Transmission electron microscopy of the compact revealed a boundary phase, which was deduced to result from reaction between Sic and barium carbide, the latter being produced by reaction between BaO and C. It is suggested that this reaction product promotes sinteri

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1985.tb10178.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Fine A12O3powder was prepared by the gas‐phase oxidation of aluminum acetyl‐acetonate. The reaction products were amorphous material at 600° and 800°C, γ‐Al2O3at 1000° and 1200°C, and δ‐Al2O3at 1400°C. The powders consisted of spherical particles from 10 to 80 nm in diameter; particle size increased with increasing reaction temperature and concentration of chel

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1985.tb10179.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

The interaction of soda‐lime glass with molten tin is of practical and scientific interest. Here the observation that the interfacial tin content of glass in contact with molten tin decreases with increasing temperature and increases with increasing oxygen pressure is confirmed and discusse

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1985.tb10180.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

The scanning electron microscope cathodoluminescence behavior of two partially stabilized zirconias is presented. Monoclinic material, either occurring on grain boundaries or produced by deformation, appears strongly luminescent, whereas in cubic‐plus‐tetragonal material grain boundaries appear dark, as do deformed regions associated with hardness indentations and wear tracks. These preliminary observations suggest that cathodoluminescence may be a valuable microstructural technique for characterizing the microstructure and deformation behavior of zirconia‐based cer

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1985.tb10181.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

A composite consisting of 20 vol% Sic whiskers in a hot‐pressed MoSi2matrix was investigated. The composite displayed an ∼100% increase inflexural strength and a 54% improvement in fracture toughness, compared to the values measured for the matrix material. The improvements are attributed to the change in the micro‐structure of the MoSi2afforded by the presence of the whi

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1985.tb10182.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

The standard procedure for determining the tensile strength and Young's modulus of single‐filament ceramic fibers (outlined in ASTM test method D‐3379‐75) was modified for accurate determination of Young's modulus, especially for fibers with larger diameters. An improved plotting method to determine the system compliance factor was developed; this method allows for variations in fiber diameter and produces more accurate Young's m

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1985.tb10183.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

A method was developed to determine compositional fluctuations in a (Ba, Pb) (Zr, Ti)O, solid solution which can exhibit two types of fluctuations. The solid solution prepared by an ordinary dry process undergoes large compositional fluctuations in both the Ba, Pb site and the Zr, Ti site. However, solid solutions prepared by solid‐solid reaction between coprecipitates of Pb2+and Ba2+and coprecipitates of Zr4+and Ti4+showed no compositional fluctuation

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1985.tb10184.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Differential scanning calorimetry and thermogravimetry were used to determine the thermodynamic properties of cerium oxalate. Hydrated cerium oxalate was found to contain 13 molecules of water and decomposed producing three thermal events corresponding to the loss of adsorbed water, water of hydration, and decomposition of anhydrous cerium oxalate to cerium oxide. Anhydrous cerium oxalate obeyed first‐order reaction kinetics where ‐In(1‐a)=kt. Reaction rates, heat capacities, and equations for the heat capacities are

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1985.tb10185.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY