Physical Properties Of Glasses Research Articles

Glass (2nd Edn)

This book covers in a comparatively small space most of the important fundamental aspects of the chemical structure and physical properties of glasses. The opening chapters discuss the nature of the glassy state, the types of bonding involved, and the stability of glasses in relation to crystallization processes.

Vibrational motion of cations in ionic glasses

Cation-site vibrational bands observed in the far-infrared spectra of the Na +, K +, Cs +, Ca 2+, and Ba 2+ metaphosphate glasses are reported, and their characteristics are discussed in terms of ion-site forces and glass physical properties.

Micrographs in ?the effect of microstructure on the physical properties of glasses in the sodium silicate system?

Micrographs in ?the effect of microstructure on the physical properties of glasses in the sodium silicate system?

The effect of microstructure on the physical properties of glasses in the sodium silicate system

The effect of microstructure on the physical properties of glasses in the sodium silicate system

A Survey of the Variations in the Physical Properties of Glass

A Survey of the Variations in the Physical Properties of Glass

The dependence of some of the physical properties of glasses made of steatite materials on their composition

The dependence of some of the physical properties of glasses made of steatite materials on their composition

A glass beam reference surface for quality control measurements

A glass beam, whose top surface is optically flat, is used as a reference surface. Supporting this beam on knife-edge supports, the configuration of the top surface is obtained from the equations for the top surface deflection. For precise linear measurements, industrial standards departments find it necessary to have accurate deflection equations so that the relative elevation from point to point on the top surface is known to parts of a μin. Presently the deflection equations are based on the simple beam theory and mean material properties. However, it is necessary to use a more rigorous deflection theory and to consider variations in material properties to obtain deflections sufficiently accurate for general application. The plane stress theory is shown, by numerical example, to yield sufficient accuracy. The effects of variations in the physical properties of glass on the deflection are significant but predictable.

New instruments for studying the physical properties of glass

New instruments for studying the physical properties of glass

Glass Formation and Properties of Glasses in the System Na2O‐B2O3‐SiO2‐TiO2

An investigation was made of the effect of TiO2 on the glassforming region and on the physical properties of glasses in the system Na2O‐B2O3‐SiO2TiO2. Glasses containing up to 45 mole % TiO2 may be formed with an alkali content of 30 mole %. At lower alkali contents (10 mole % Na2O) glasses may be formed containing up to 22 mole % TiO2. The way in which the coefficient of linear thermal expansion and the transformation and softening temperatures are affected by TiO2 additions has been determined.

Physical properties of glasses I

AbstractThe paper is an introduction to a series of studies about the density and other physical properties of glasses.

X‐RAY DIFFRACTION STUDY OF SODA‐BORIC OXIDE GLASS *

AbstractX‐ray diffraction patterns have been made of three samples of soda‐boric oxide glass of the following molal compositions: 0.114 Na2O, 0.225 Na2O, and 0.333 Na2O. The patterns were made in an evacuated camera, using MoK α radiation monochromatic by reflection from rock salt. Radial distribution curves for the three compositions were obtained by Fourier analysis. The first peak of the distribution curves is due to the boron‐oxygen separation. The distances are 1.37, 1.42, and 1.48A. From the peak areas, the number of oxygens about a boron is found to be 3.2, 3.7, and 3.9. The continuous change, both in interatomic distance and number of surrounding oxygens, indicates that the borons are partly in triangular and partly in tetrahedral coordination, the fraction in the latter increasing with increase of soda. Six oxygens about each sodium at 2.4A and from five to six oxygens about each oxygen at 2.4A are consistent with the distribution curves. The results can be interpreted in terms of a random network picture of vitreous soda‐boric oxide, in which the borons are bonded either to three or four oxygens and the sodium atoms are randomly distributed in holes in the boron‐oxygen network. Maxima and minima in the physical properties of glasses containing boric oxide and soda are explained in terms of the ability of the boron atom to change to tetrahedral coordination when some oxide such as Na2O is present to supply the necessary extra oxygen.

The physical properties of glasses. The relationship to chemical composition and mode of preparation

The first page of this article is displayed as the abstract.

II. Refractive indices of glass

Most of the following determinations were made two years ago.They were not published at once, because the results showed more variation than was expected. They are now made known for two reasons. First, most of the glasses examined are articles of commerce, and can be readily obtained by any person experimenting upon the physical properties of glass; these glasses only vary within narrow limits, and their variations may be approximately allowed for by a knowledge of their density. Second, most of the prisms having three angles from each of which determinations were made, the probable error of the mean is very small, and any error of the nature of a blunder is certainly detected. The form in which to present these results was a matter of much consideration. A curve giving the refractive indices directly is unsuitable, for the errors of observation are less than the errors of curve-drawing would be. The theory of dispersion is not in a position to furnish a satisfactory rational formula.