bluuebunny/crossref_metadata_2025 huggingface dataset:
MICROSTRENGTH OF GLASS *
Authors: Powel H. E. , Preston F. W.
Published: June 2006

Abstract

It is shown experimentally that if a minute area of a large piece of glass is tested for tensile strength, the stress supported is comparable with that of fine glass fibers and is some fifty or one hundred times the “strength” of the large piece tested in any of the ordinary ways. The experiment consists in pressing a small steel ball upon the glass surface, and so stressing, in tension, a minute annular zone around the circle of contact.
CONTINUOUS TANK FOR HAND‐BLOWN GLASS *
Authors: Schwalbe F. G.
Published: June 2006

Abstract

The quality of glass obtainable from a continuous glassmelting furnace is dependent on raw materials, fuels, furnace design and operation, and skill in the art of gathering and manipulating molten glass. Of these requirements, the content of the present paper is limited to information on furnace design and construction and its effect on the ultimate quality of the glass that can be produced when proper fuels, raw materials, and labor are employed.
CONE 015 RELIEF ENAMELS FOR DECORATING VITREOUS CHINA *
Authors: Voorhies John H.
Published: June 2006

Abstract

Relief enamels must remain in relief and not flow down during maturing fire. They must also have adequate acid and abrasion resistance; they should not craze and they should accommodate as wide a color range as possible. The relief enamel developed in this study satisfies these various qualifications.
MINERALS AND MINERAL RELATIONSHIPS OF THE CLAY MINERALS *
Authors: Ross Clarence S.
Published: June 2006

The invitation to be the Edward Orton, Jr., Fellow Lecturer of the American Ceramic Society for 1945 is a very great honor and a privilege which one interested in the mineralogy of clays must heartily appreciate. Dr. Orton was a geologist as well as a founder of this Society, and no doubt in issuing this invitation you had in mind the maintenance of this historic relationship. Those of us who follow him cannot add to that relationship, but I hope that I can help to foster it. Perhaps not all geologists know of this common ground between ceramics and geology as you do, and no doubt you would have me remind my geologic colleagues of this and of the mutual contributions which its maintenance entails.

Another common bond of interest is that ceramists have made use of mineralogic and petrographic techniques to an extent not matched in any other applied science. In particular, they have utilized the petrographic microscope, and ceramists and mineralogists alike have found in X rays a wonderful new method of research. Clays, the subject of this lecture, should provide a common meeting ground and one which no doubt would win the hearty approval of Dr. Orton.
EFFECT OF GROUND COATS ON REFLECTANCE OF COVER ENAMELS *
Authors: Stufft and P. C. , Spencer‐Strong G. H.
Published: June 2006

Abstract

The problem of color variation in white cover‐coat enamels has received considerable attention, but variations in color due to base coat have had little or no consideration. An attempt was made to determine the effect of the base coat by comparing color variations in opaque and superopaque enamels applied over blue, white, gray, red, yellow, and green base coats in weights ranging from 10 to 120 gm. per sq. ft.

The resultant finishes were compared visually and with the aid of the Hunter multipurpose reflectometer. Over the entire range studied, the base coat was found to have a marked effect on the color characteristics of the finish coat. This is true particularly in the lower ranges of application including normal production application weights. Base coats that decreased the reflectance of the cover coat in the blue field, were found to give higher apparent opacity than those which maintained a relatively high blue reflectance.
BENEFICATION OF SOUTH CAROLINA SILLIMANITE SCHISTS *
Authors: Rampacek Carl , Clemmons B. H. , Clemmer J. Bruce
Published: June 2006

Abstract

Laboratory batch and pilot‐plant tests have demonstrated that the South Carolina sillimanite schists are amenable to beneficiation by recognized mineral‐dressing methods. Flotation tests on a number of small samples indicate that the schists containing prismatic sillimanite respond more readily to treatment than those containing fibrous sillimanite.

Batch testing of the small samples was supplemented by continuous trial runs in the laboratory pilot plant on a schist from the Pelzer, South Carolina, area. The schist, containing 17% prismatic sillimanite, was ground to 20‐mesh and concentrated by a combination of tabling and flotation supplemented by magnetic separation of the concentrates. In an average test, 82% of the sillimanite was recovered in concentrates which contained 99% sillimanite and 1.04% total ferric oxide.

The concentrates were tested at the Electrotechnical Laboratory of the Bureau of Mines, Norris, Tennessee, for refractory properties. Standard‐size brick made from the concentrates met A.S.T.M. and the more severe Navy reheat‐test specifications for super‐duty refractories.

Summary of Testing of Sillimanite Concentrates

The beneficiated South Carolina concentrate was tested at the Electrotechnical Laboratory of the Bureau of Mines at Norris, Tennessee. Standard‐size brick that were power pressed and then fired five hours at 1600°C. showed only a slight volume change, thus meeting the A.S.T.M. and the more severe Navy reheat specifications for superduty refractories. All types of commercial as well as experimental refractories have been tested at the Electrotechnical Laboratory. Brick made from South Carolina sillimanite had the highest load resistance of any alumina‐silica refractories tested except electric‐furnace cast corundum‐mullite block.

After firing, the brick were mottled brown in color. Acid leaching of the concentrates removes some of the iron compounds on the surfaces of the grains and improves the color. Brick made from acid‐leached sillimanite may be of value in glasshouse refractories.
DIMENSIONAL COORDINATION *
Authors: Adams M. W. , Bradley† Prentice
Published: June 2006

Abstract

A method is described that has been developed by American Standards Association Project A62 for coordinating standard sizes of building products and for correlating the layout and design of buildings. Applications of the method to masonry and windows are discussed and layouts are shown.
CHEMICAL DURABILITY OF PORCELAIN ENAMELS *
Authors: Cook Ralph L. , Andrews Andrew I.
Published: June 2006

Abstract

The resistance of representative porcelain enamel surfaces to the chemical attack of different concentrations of various solutions was investigated in considerable detail. Cylindrical cup‐shaped samples were coated with (1) a ground coat, (2) a white fluoride cover enamel, (3) a white antimony cover enamel, (4) a white zirconium cover enamel, (5) an acid‐resistant white cover enamel, (6) a sign blue cover enamel, (7) a blue zirconium enamel, and (8) a chemical acidproof blue cover enamel. The loss in weight of these enamel surfaces, after exposure to chemical attack, was determined at definite time intervals. The solutions studied consisted of different concentrations of the inorganic acids, alkalis, several organic acids, as well as selected salt solutions at both room and boiling temperatures.

Numerous curves are presented showing the comparative chemical durability of the various porcelain enamel surfaces in which the cumulative loss in weight is plotted against time. Several photomicrographs show the nature and type of chemical attack on the different surfaces.

The porcelain enamel surfaces showed considerable variation in their resistance to the chemical attack of the various solutions. All of the porcelain enamels were, in general, resistant to attack at room temperature by the alkali and salt solutions. The acid‐resistant and acidproof enamels were resistant to the action of both inorganic and organic acids at room and at boiling temperatures; a wide variance, however, was shown in the comparative acid resistance of the non‐acid‐resisting enamel to the attack of either organic acids or inorganic acids at room temperature. AU porcelain enamels showed equally low resistance to boiling alkali solutions, but some of the enamel surfaces were attacked markedly by the boiling salt solutions.
USE OF WOOD ASH IN A LOW‐FIRE MAT GLAZE *
Authors: Thurn Haldon L.
Published: June 2006

Abstract

The development of a low‐fire mat glaze for studio use is described in which part of the fluxes and silica and alumina are supplied by the use of wood ash. The materials required are simple and readily obtained and the glaze is easy to apply. One firing is eliminated by its application to the green ware, and the firing range is from cones 04 to 02.

In the glaze described, wood ash supplies a part of the silica and alumina çontent along with certain fluxes of which calcium is the more important.

In the alumina‐type mats, wood ash produces a texture similar to that of the stoneware glaze which was the source of inspiration.

The glaze can be applied by brushing, pouring, or spraying on the green ware or on bisque‐fire ware; brushing on the unfired ware is preferable. An over‐thick application destroys the beauty of the glaze.

The glaze does not crawl and it is self‐healing when drying cracks appear; no cracks, however, have appeared when the glaze has been used on green ware. Handsome colors can be produced with the use of very little coloring oxide.
FLOW LINES IN A CONTINUOUS MELTING GLASS FURNACE AS DETERMINED BY COBALT OXIDE AND PICTURED ON COLOR PHOTOGRAPHS *
Authors: Lenz Vernon W.
Published: June 2006

Abstract

The results of a study of glass flow in a direct‐fired, continuous melting tank can be used to establish control testing schedules and tank dimensional relationships. Three primary convection spirals are indicated. Normal convection currents produce good mixing. The methods used in making the study are explained. The use of a coloring agent and color photographs as a means of recording the results are presented as a new technique for studies of this type.
TESTING OF CHROME‐MAGNESITE BRICK FOR RESISTANCE TO IRON OXIDE BURSTING *
Authors: Zerfoss S. , Davis H. M.
Published: June 2006

Abstract

The probable mechanism of the iron oxide bursting of chrome‐magnesite brick is discussed. An attempt was made to duplicate this effect in the laboratory. Results indicate that the bursting can be simulated in a laboratory experiment providing the atmosphere of the furnace is such that the penetrating iron oxide liquid is rich in magnetite. A test is proposed for characterizing the bursting resistance of various brick.
X‐RAY DIFFRACTION DATA FOR COMPOUNDS IN THE SYSTEM CaO‐MgO‐SiO2*
Authors: Clark C. Burton
Published: June 2006

Abstract

X‐ray diffraction data by the powder method for compounds in the system CaO–MgO–SiO2 are widely scattered in the literature. In certain instances, there is need of revision of the earlier data because of improvement in equipment and technique. X‐ray patterns have therefore been made, and the data are here presented covering nineteen of the compounds in the system CaO–MgO–SiO2. These represent all the known compounds which are stable, and several which are metastable, at room temperature.
RESISTANCE OF PLATE GLASS TO ALKALINE SOLUTIONS *
Authors: Tarnopol M. S. , Junge A. E.
Published: June 2006

Abstract

The resistance of polished plate glass to sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, and sodium pyrophosphate was studied at various concentrations and temperatures. Test results showed (1) that the hydroxides are less corrosive than many alkaline salts; (2) that temperature has a marked effect on the rate of corrosion; (3) that increasing the solution above 10% does not alter the rate of attack appreciably; and (4) that the amount of stain on glass cannot be used as a measure of the amount of attack.
COMPARISON OF EFFECT OF TiO2 AND PbO ON LIGHT ABSORPTION OF SOME COLORED GLASSES *
Authors: Colbert William
Published: June 2006

Abstract

Series of glasses have been melted with TiO2 or PbO as major constituents. To each member of the series, equal amounts of one of the following coloring ions have been added: Fe, Cu, U, Ce, and Mn. Complete spectrophotometric curves in the visible region have been obtained for the glasses. The color imparted by the ions to the glass is correlated with the position of the ion taken in the glass structure and conclusions are drawn showing that TiO2 and PbO additions to glasses make it easier for the coloring ions to take part in the glass network.
COMPARISON OF EFFECT OF TiO2 AND PbO ON REFRACTIVE INDEX OF GLASSES *
Authors: Colbert William
Published: June 2006

Abstract

Densities and refractive indices were measured on two parallel series of glasses, one containing TiO2 and the other PbO. It was found that for equal mol per cent additions of TiO2 and PbO the glasses have quite similar refractive indices. From the data given, the molecular refractivities were calculated, and a marked similarity was found in the effects produced by TiO2 and PbO.
USE OF SODA FELDSPAR IN WHITEWARE BODIES *
Authors: Loomis George A. , Blackburn A. R.
Published: June 2006

Abstract

A comparative study is presented of a soda feldspar produced by a flotation process and of two potash feldspars when tested alone and made up in semivitreous and vitreous bodies. The investigation was divided into two parts, (1) a laboratory study and (2) plant trials on semivitreous dinnerware and on vitreous sanitary porcelain.

From the results of the investigation, it was concluded that (1) it should be possible to substitute soda feldspar for North Carolina potash feldspar in semivitreous bodies containing not more than 12% feldspar, on an equal basis, with no significant change in properties except possibly crazing resistance; where crazing occurs, a slight modification of the regular glaze to give it a lower thermal expansion should correct the trouble; the formula of one modified glaze for this purpose is suggested; and (2) the substitution of soda feldspar for potash feldspar in sanitary porcelain and other similar vitreous whiteware bodies will doubtless require a reduction in amount in order to duplicate the vitrification and other properties of the potash‐feldspar body in use; a modification of the regular glaze to fit the soda‐feldspar body will probably be required; and the castability and control of casting slips should not be affected by the use of soda feldspar in place of potash feldspar.
SILICONES: NEW SILICA‐BASED PLASTICS OF INTEREST TO THE CERAMIC INDUSTRY *
Authors: Bass Shailer L. , Hyde J. F. , McGregor R. R.
Published: June 2006

Abstract

Silicones derive many of their most useful properties from the inorganic nature of the silicon‐to‐oxygen links which they possess in common with glass and mineral silicates. They derive plasticity, solubility, and water repellency from the organic radicals attached to their basic structures. The chemical nature of silicon in combination with oxygen permits the development of a variety of silicone compounds in various physical forms ranging from fluids through gels and resins to elastic materials. Because of their ease of application, their general heat stability, and chemical inertness, they are natural complements to ceramic bodies in many applications. They are already proving their usefulness with these materials in the production of new types of electrical insulation, in the surface treatment of glass and ceramic products, and as auxiliary dielectrics for use with ceramic insulating forms.
EFFECT OF COMPOUNDS OF SULFUR ON REHEAT VOLUME CHANGE OF FIRE‐CLAY AND HIGH‐ALUMINA REFRACTORIES
Authors: Lesar A. R. , Krinbill C. A. , Keller W. D. , Bradle R. S.
Published: June 2006

Abstract

A process is described for controlling the reheat volume of fire‐clay and high‐alumina refractory products. The volume change of a fire‐clay or high‐alumina refractory body fired at a normal firing temperature can be regulated for use in service at a higher temperature by the addition of a definite quantity of a water‐soluble compound of sulfur. Compounds of sulfur that are insoluble in water are not effective for this process. The process is relatively inexpensive and can be applied to any standard refractory manufacturing procedure.
COMPARISON OF REPEATED REHEAT TESTS OF VARIOUS GRADES OF FIREBRICK WITH SERVICE RESULTS
Authors: Tredennick W. T. , Kelly J. F. , Burt R. C.
Published: June 2006

Abstract

Representative brands of Navy‐approved class A brick (60% alumina), class B brick (superduty), and special firebrick (in a price group above the 60% alumina brick) were installed in a naval boiler operating continuously at the Naval Boiler and Turbine Laboratory. The permanent volume change of the various brands, subjected to repeated reheat tests at 2912°F., is compared with their service life.
STEATITE GLAZES
Authors: Thiess L. E.
Published: June 2006

Abstract

A number of high‐fire and low‐fire steatite glazes were investigated, and their mechanical and electrical properties are given. Special tests were conducted on some of these glazes to determine the important property of thermal‐shock resistance.
EFFEC T OF MOLYBDENUM AND OTHER OXIDES ON SURFACE TENSION OF SILICATE MELTS AND ON PROPERTIES OF REFRACTORIES AND ABRASIVES*
Authors: AMBERC C. R.
Published: June 2006

Abstract

A modification of the drop‐weight method of measuring surface tension in molten silicates is used to determine the effect of small additions of MoO3, V2O6, WO3, Sb2O3, Ni3O4, CO3O3, MnO2, UO2, and As2O3 to a glaze, a glass, and an enamel composition. Molybdenum trioxide is found to be an outstanding surface‐tension reducer or wetting agent. The use of lowered surface tension in coatings and bonds has made possible oxidationresistant graphite crucibles and silicon carbide refractories; harder, long‐lived, free‐cutting abrasive wheels; and coated abrasive grain with improved adherence to glue.
UVERITE—A MILL ADDITION OPACIFIER FOR PORCELAIN ENAMEL*
Authors: Harbert C. J. , Iliff John W.
Published: June 2006

Abstract

Uverite is the trade name for an antimony‐titanium opacifier, having an approximate formula of 7CaO·CaF2·6TiO2·2Sb2O5. When compared with tin oxide in a range of commercial enamels, it has proved to be equivalent in its effect on opacity, color, gloss, firing range, general workability, and durability.
HERMETICALLY SEALED STEATITE*
Authors: Hausner Henry H.
Published: June 2006

Abstract

The problem of sealing metals to steatite are similar to those encountered in glass‐metal seals but it is more difficult because four different materials must be joined, namely, steatite, glaze, metal oxide, and metal. The thermal expansion coefficient of these materials must obtain in a certain relationship to guarantee a hermetic seal. The use of high‐chromium steel for sealing purposes and the properties of this steel are described. Some design criteria for hermetically sealing steatite bushings are discussed and hints on manufacturing these bushings are given.
USE OF BROMATE IN VOLUMETRIC ANALYSIS: IX, DETERMINATION OF ARSENIC AND ANTIMONY BY THE GYÖRY METHOD*
Authors: Smith G. Frederick
Published: June 2006

Abstract

The determination of arsenic and of antimony by the oxidation of the hydrochloric acid solutions of their tervalent forms using standard bromate as oxidant by the Györy method has long been a preferred procedure. This method involves the use of strongly acid, hot solutions and nonreversible internal dye‐stuff indicators. Difficulties result from the instability of the indicators under the required conditions. The published improvements as applied to the Györy method are discussed and evaluated. The new study of the old procedure shows that the use of a hot solution is not required. The experimental proof of this conclusion is given, and the use of the “electron beam sectrometer” and a modified “dead stop” equivalence‐point determination has been applied to establish the concordance between the potentiometric and visual indicator applications. The performance of the various applicable internal indicators has been described and those preferred are specified.
EFFECT OF IRON ON FLUORESCENCE IN GLASS*
Authors: Thorington Luke , Russell Ralston , Silverman Alexander
Published: June 2006

The mechanism of fluorescence as it occurs in a uranium glass when irradiated with ultraviolet light is discussed with special reference to factors affecting both the intensity and spectral distribution of the fluorescence. The destructive effect of iron on the fluorescence of the glass is discussed and is illustrated by spectral absorption curves and by recorded fluorescence spectra. Conclusions based on these data indicate that iron not only absorbs a large portion of the exciting radiation, thereby decreasing the fluorescence emission, but also re‐emits this absorbed radiation in the infrared, thus bringing about the infrared quenching of the fluorescence. Iron also causes an electrical disturbance around the fluorescing centers and is apparently capable of preventing the absorption of exciting radiation by these centers, further decreasing the intensity of fluorescence. A slight shift of the fluorescence spectrum toward shorter wave lengths is brought about by the presence of iron and is evidence of a weakening of the binding forces within the glass.
EFFECT OF CHEMICAL COMPOSITION ON REFRACTIVE INDEX AND ABBE VALUE FOR TERNARY SILICATE GLASS SYSTEMS*
Authors: Huggins Maurice L , Sun Kuan‐Han , Welch Ruth M.
Published: June 2006

A general procedure (based on previously published equations and constants) is outlined for the production of a chart showing the relationship between refractive index, Abbe value, and composition for ternary silicate glass systems. As an example, such a chart is presented for the Na2O–CaO–SiO2 system.
STIFFENING EFFECT OF PORCELAIN ENAMEL ON SHEET IRON: I–II*
Authors: Wolford Don S. , Selby Glenn E.
Published: June 2006

The stiffening effect of porcelain enamel is important in applications involving flat surfaces, such as panels, signs, tabletops, cabinets, refrigerators, and stoves. The purpose of this paper is to report on several investigations evaluating the effect.

Bending tests were made on small flat specimens of 18‐ to 28‐gauge sheet iron coated on both sides with porcelain enamel ranging in thickness from 0.004 to 0.025 in. per side. Substantial increases in stiffness reaching as high as 1500% for 28‐gauge steel with 0.025 in. of enamel on each side are shown in comparisons between bare and enameled specimens. The increases in ultimate bending strength range to 500%, but the usable increase is somewhat less. Bending tests were made on porcelain‐enameled corrugated sheets, which showed somewhat smaller increases in stiffness and bending strength due to enameling. The minimum thickness of base metal and maximum thickness of enamel are, of course, governed by practical considerations, such as the resistance necessary against chipping and the ability to maintain flatness during firing, which also depend on shape and proportions of the product.

A method is given for computing the bending properties of flat sheets and formed sections by means of the usual formulas of mechanics with correction factors for the porcelain enamel. Conversion curves are shown by which bare and enameled sheets may be compared.
INFLUENCE OF BATCH MIXING TIME AND BATCH GRAIN SIZE ON HOMOGENEITY OF A SODA‐LIME‐SILICA GLASS*
Authors: Tooley F. V. , Tiede R. L.
Published: June 2006

Abstract

Density‐spread determinations were made on a series of melts of a soda‐lime‐silica glass employing batches compounded from raw materials varying in particle size from 20‐ to 60‐mesh to minus 200‐mesh, which had been mixed by tumbling for one, ten, or thirty minutes. The two melting techniques employed were (1) melting for sixteen hours in a stationary platinum crucible at 1400°C. under conditions of even temperature distribution and consequently a minimum of convection mixing and (2) melting for four hours at 1400°C. in a rotating tilted crucible; this condition was intended to simulate convection mixing

Under the experimental conditions employed, it was found that (1) batch mixing time has relatively little effect on the homogenizing rate, (2) homogenization increases rapidly with decrease in grain size, and (3) in all cases the 4‐hour melting treatment with moderate mixing gives better homogeneity than sixteen hours melting time in a stationary crucible, this effect increasing with decrease in grain size. No significant difference in glass homogeneity resulted from three different methods of mixing, namely, tumbling, ball milling, and mixing in a muller‐type mixer, although the homogenizing influence imposed probably was sufficient to mask any differences in uniformity of mixing that might have existed.
I. DELAYED THERMAL CONTRACTION AND CRAZING OF CERAMIC GLAZES
Authors: Mattyasovszky‐Zsolnay L.
Published: June 2006

Abstract

Experimental rods, glazed with sixteen different glazes, representing various possible types of earthenware glazes, were tested in the Steger stress‐measuring apparatus before and after five years of airtight storage. The original stress of all the glazes remained constant within the limit of accuracy of the method, indicating that the delayed thermal contraction of the glazes is negligible.
PHYSICAL PROPERTIES OF SOME HIGH‐TEMPERATURE REFRACTORY COMPOSITIONS*
Authors: Pole Gordon R. , Beinlich Alfred W. , Gilbert Nathan
Published: June 2006

Abstract

In the course of an investigation that involved a study of pyrochemical reactions, it was necessary to develop a refractory that could be used satisfactorily at temperatures in the range of 1800° to 2200°C. It was found that calcined magnesia (96%, MgO) or electrically fused magnesia (98% MgO) could be bonded adequately by mixing sized aggregates with 2.5%, by weight of calcined sea‐water magnesia and wetting with a 24° Bé. solution of magnesium chloride Large shapes of these compositions fired at 1450°C. were satisfactory for use in the required temperature range.

A small‐scale study OF the properties of various refractory bodies showed that compositions containing relatively pure limestone or dolomite readily hydrated in water even after firing to 2100°C. and were unsuitable for refractory use. The addition of silica, alumina, zirconia, chromic oxide, or combinations of these oxides to dolomite or limestone resulted in a refractory stable against hydration.

The inversion of zirconia was reduced appreciably by the addition of 5% magnesia. Bodies containing BaO·ZrO2 and CaO·ZrO2 were found to be stable after firing to 2100°C. with no inversion up to 1200°C. and with a coefficient of expansion less than that of electrically fused magnesia.

Small‐ and large‐scale tests of an MgO·Cr2O3 spinel composition showed this material to be highly refractory with a low coefficient of expansion; the compound, however, dissociates and loses Cr2O3 above 1700°C. While the small‐scale tests disclosed a number of compositions which show promise as high‐temperature refractories, their full evaluation for use on a large scale was not made.
QUANTITATIVE SPECTROGRAPHIC ANALYSIS OF CERAMIC MATERIALS*
Authors: Smith R. W. , Hoagbin J. E.
Published: June 2006

Abstract

A rapid spectrographic method for the quantitative analysis of ceramic materials has been developed. Samples as small as 50 mg. may be analyzed completely, and the speed is sufficient for the routine control of mixing, grinding, and other processes. The special problems of sampling and mixing are discussed in detail. Procedures are given for carrying out the determinations of soda and silica in alumina, but the method is equally applicable to other elements and other matrices. Numerical data are given showing the accuracy and precision to be expected in routine work.
RELATION OF ENAMELING IRON PREPARATION AND ACCESSORY CONDITIONS TO COPPERHEAD‐TYPE DEFECTS*
Authors: Pfeiffer W. H. , Sheldon R. S.
Published: June 2006

Abstract

The tendency of blue ground‐coat enamels to copperhead is shown to be related to residual iron salts formed on the surfaces of enameling iron sheets in sulfuric acid pickling. Ferrous sulfate generated in the pickling oxidizes and hydrolyzes readily into compounds which are not soluble in cyanide neutralizer. These effects may be retarded by keeping the solutions between the sulfuric acid and the neutralizer slightly acid and by minimizing the time in these solutions and the exposure to air in transferring between them. The determination of these conditions and the establishment of satisfactory procedures in the production process are described. Some accessory conditions which affect copperheading are also included.
STRESS‐STRAIN RELATIONS IN CERAMIC MATERIALS*
Authors: Lassettre Marjorie , Everhart J. O.
Published: June 2006

Abstract

The electric strain gauge was used to study the deformation of several types of ceramic materials under stress. It was found that they behaved as elastic materials. The hard‐fired materials exhibit straight‐line deformation to failure while the softer‐fired have a proportional elastic limit beyond which the stress‐strain curve deviates from a straight line. Data indicate that engineering formulas based on elastic materials may be applied to ceramic materials.
DIELECTRIC PROPERTIES OF GLASSES AT ULTRA‐HIGH FREQUENCIES AND THEIR RELATION TO COMPOSITION *
Authors: Navias Louis , Green F. L.
Published: June 2006

Abstract

The dielectric constants and dielectric losses of 104 glasses of a wide range of compositions have been measured at 10‐cm. and 3‐cm. wave lengths by the resonating cavity method (3000 and 10,000 megacycles, respectively). By correlating the power‐factor data with the compositions of these glasses, the authors propose a qualitative explanation of the mechanisms producing energy absorption and dielectric losses in the microwave range. These mechanisms are determined by the nature of the bonds joining atoms and ions in the randomly oriented atomic networks of glasses.

The rigid and continuous networks of SiO2 and B2O3 glasses are relatively transparent to centimeter wave lengths. Energy absorption and dielectric losses are low. Addition of network‐modifying oxides yields glasses of greater energy absorption owing to the oscillation of the interstitial ions thus introduced. Increasing the content of any one of these ions in a glass results in higher losses while the coexistence of a variety of these ions generally results in lower losses.

Alkali ions in glasses give rise to high losses, which increase as the number of ions present increases. Glasses containing a combination of alkalis show lower losses than the equivalent compositions with only one alkali. Divalent ions do not contribute as much to losses as alkalis, but high power factors are shown by glasses with high BaO or PbO contents. Using combinations of these oxides instead of only one, slight reductions in power factor are effected. Dissimilar interstitial ions interact in ultra‐high frequency fields with the result that energy absorption is reduced. The losses of high‐lead glasses are thus reduced by alkalis and, on the other hand, the presence of RO lowers the losses of glasses containing R2O. Alumina increases the dielectric losses of glasses in much the same manner as other network modifiers.
FACTORS GOVERNING ADHERENCE OF ENAMELS APPLIED TO SHEET IRON *
Authors: Johnson L. A. , Howe E. E.
Published: June 2006

Abstract

A series of tests were conducted to ascertain the effect of nickel deposition and firing variations upon the adherence of enamels applied to special enameling sheets. Limits were established for securing optimum adherence of zirconium‐opacifid white, antimony‐molybdenum‐opacified white, and commercial blue ground‐coat enamels.
NOTES ON REACTION BETWEEN MgO AND VARIOUS TYPES OF REFRACTORIES *
Authors: Norton C. L. , Hooper Bradford
Published: June 2006

Abstract

Samples of high‐heat duty, superduty, 60% Al2O3, 70% Al2O3, 90% Al2O3, fused‐alumina, kaolin base, kyanite base, chrome magnesite, silicon carbide, zircon, and chrome‐magnesite compositions were tested for reaction with MgO at temperatures of 2200°, 2600°, and 2800°F. (1205°, 1425°, and 1540°C.). Silicon carbide and zircon refractories showed a slight reaction at 2800°F. and none at 2600°F. or at 2200°F. Commercial grades of firebrick containing 60% or more of Al2O3 in contact with powdered magnesia showed no reaction up to 2800°F.
OBSERVATIONS ON THE SHELLING OF CHECKER‐BRICK*
Authors: Petrie E. C. , Brown D. P.
Published: June 2006

Abstract

Brick installed in glass‐tank checkers, removed, cleaned, and returned to service at higher operating temperatures showed excessive bloating and shelling; checker‐brick from open‐hearth checkers were affected in a similar manner. Chemical analyses of the several samples indicated that pickup of excessive alkalies may be responsible. The alkalies apparently were derived from either the batch, the fuel, or the ground water occurring under the checker settings.
SURFACE TENSION OF COMPOSITIONS IN THE SYSTEMS PbO‐B2O3 AND PbO‐SiO2*
Authors: Shartsis L. , Spinner S. , Smock A. W.
Published: June 2006

Abstract

The surface tension of a series of compositions ranging from 0 to 100% PbO in the system PbO‐B2O3 and of compositions ranging from 0 to 35% SiO2 in the system PbO‐SiO2, was measured by a modification of the anchor ring method. The volatility and changes in composition of members of each system on heating were found to be related to the surface tension and its change with composition. Some correlation between the temperature coefficient of surface tension and expansivity was noted.
DETERMINATION OF COMPRESSIVE STRESS PRESENT IN PORCELAIN ENAMEL ON SHEET IRON*
Authors: Bryant E. E. , Ammon M. G.
Published: June 2006

Abstract

A method for determining comparative compressive stress produced in porcelain enamel on sheet iron is described. The method consists of preparation of laboratory samples under carefully selected and controlled conditions and measurement of the warpage produced in the sample due to application of enamel on one side. Data obtained by the above method are compared with expansion curves. Several methods of analyzing the curves fail to produce correlation between expansion as determined on frit samples and compression in the porcelain enamel as indicated by the warp of sample plates. It is concluded that expansion curves on frit samples are not a satisfactory means of evaluating compressive stress in the porcelain enamel coating on sheet iron.
ELECTRODE FUNCTION (PH RESPONSE) OF THE SODA‐SILICA GLASSES*
Authors: Rynders Gerald F. , Grauer Oscar II. , Hubbard Donald
Published: June 2006

Abstract

A scries of Na2O‐SiO2 glasses was studied for durability, hygroscopicity, glass‐electrode function, and apparent response to [Na +]. These glasses showed three distinct regions of durability characteristics at pH 4.6: (1) below 81% of SiO2, where the glass was carried into solution; (2) between 81 and 89.5% of SiO2, where differential solution of the constituents of the glass left a swollen silica‐rich layer; and (3) a region in which greatly reduced attack was indicated. Glass electrodes of low silica content having poor chemical durability and high hygroscopicity exhibited large voltage departures approaching the values of a “punctured” mercury‐filled electrode and a calomel half cell. The apparent response to [Na+] ranged from 9 to 339 mv. per pNa for the glasses of 82.6 and 56.6% of SiO2, respectively.
OF ANALYTICAL CONTROL FOR SILICA BRICK*
Authors: Rozsa J. T.
Published: June 2006

Abstract

The prevalent use of silica brick has focused attention upon the need for control and improvement in quality. A review of the methods available reveals that many laboratory tests have been developed to avert expensive trial testing. It is significant, however, that the chemical knowledge of this product has lagged owing to (1) difficulty in sampling, (2) the tedious and time‐consuming aspects of wet chemical methods, and (3) the consequent lack of knowledge of the deleterious effects of certain secondary constituents. One of the newer analytical tools is the spectrograph. A total‐energy method has been developed to permit analysis of A12O3, MgO, Fe2O3, CaO, Na2O, TiO2, K2O, ZrO2, MnO2, and Li2O. Thirty minutes are required for sample preparation and twenty‐five minutes for the spectrographic process. Present accuracy is well within production limits. This method is also suitable for the analysis of glass sand.
SONIC METHOD FOR DETERMINING YOUNG'S MODULUS OF ELASTICITY*
Authors: Baab Kenneth A. , Kranbr Hobart M.
Published: June 2006

Abstract

The instrument and methods for measuring the resonant frequencies of brick and for calculating Young's modulus of elasticity are described. Charts correlate elasticity and other properties of fired brick with firing temperatures. Results indicate that the sonic method of determining the modulus of elasticity is suitable for determining the degree of firing that a series of brick has undergone.
USE OF TORSIONAL STRESSES FOR OBSERVING HIGH‐TEMPERATURE CHARACTERISTICS OF CERAMIC MATERIALS*
Authors: Decker Alfred R. , Royal Herbert F.
Published: June 2006

Abstract

A method is described for testing ceramic specimens under torsional stresses at temperatures to 2500 °F. With simple apparatus and minimum time, consistent values are obtained for modulus of rigidity, Poisson's ratio (when the modulus of elasticity is known), tensile (torsion) strength, torque‐twist graph, approximate softening temperature, plastic deformation, and short‐time creep rate. The results are in satisfactory agreement with tensile test, bending test, and long‐time creep‐rate results and thus provide a quick means of making a preliminary selection of promising compositions for more extensive testing. Among the advantages of torsion testing are freedom from error caused by thermal expansion, absence of need for close dimensional tolerances, simplicity of specimen installation in grips, and the ability to make deformation measurements outside the furnace on the cool end of the specimen. Data for a sillimanite body and a beryl‐lia body illustrate the types of information given by the method. The beryllia body has more suitable high‐temperature characteristics.
FACTORS AFFECTING REPRODUCIBILITY OF FLOW‐BUTTON TEST*
Authors: Plankbnhorn W. J.
Published: June 2006

Abstract

Pellets formed from dry‐milled ground‐coat frits of the conventional cobalt type were used to study the factors influencing the flow characteristics of enamel fusion buttons at temperatures above their softening points. To insure reproducible results it was necessary to control accurately (1) the materials being tested, (2) the temperature, (3) the time, and (4) the weight of the sample. Reasonable variations in the gauge of the metal holding plate and the coating applied to protect the plate did not greatly affect the dimensions of the fired buttons. Little difference in the flow of ground‐coat fusion buttons was noted for variations in either particle size, fineness distribution, forming pressures, or height of the pellets.
INVESTIGATION OF THE EFFECT OF LOW‐FIRED GROGS ON PROPERTIES OF SOFT‐MUD BRICK*
Authors: Bowman R. R. , Burdick R. B.
Published: June 2006

Abstract

Soft‐mud brick were made from various mixtures of Hudson River clay and grog prepared by calcining the clay at 500°, 700°, and 900°C., and rate of drying tests were carried out. The brick were fired to cones 012, 08, and 04, and a special fast fire to cone 08 was also run. The various properties were compared with those of regular mix brick and all‐clay brick. Brick made of a mixture of clay with 35% of 900°C. grog had particularly satisfactory properties such as to afford definite advantages as regards faster drying and accelerated firing.
APPLICATION OF REPLICA TECHNIQUES TO THE STUDY OF CERAMIC SURFACES WITH THE OPTICAL MICROSCOPE*
Authors: Allen A. W. , Friedberg A. L.
Published: June 2006

Abstract

A method of preparing transparent replicas of ceramic surfaces for study with the optical microscope is described. Photomicrographs and projection prints of surface details which are difficult to analyze microscopically by direct methods of observation are presented. The surface‐replica material used will penetrate openings as small as the limit of resolving power of the ordinary light microscope and can be studied effectively by (1) direct observation by transmitted light in a microscope having the simplest available optical system, (2) used as a transparency and projected on a screen, and (3) placed in a photographic enlarger and used as a negative to produce direct projection photographic prints. The method is particularly useful when duplicate samples of the same specimen are required, when the specimen cannot be destroyed by grinding or cutting, or when reflected light from a surface destroys contrast in detail.
IMPROVING THE QUALITY OF EXTRUDED MILL BRICK*
Authors: SCHURECHT† H. G.
Published: June 2006

Abstract

In the production of extruded brick for lining ball mills, unevenness of the brick such as (1) bow, (2) diagonal twist, (3) sunken faces, (4) depressed and bulged ends, and (5) underfired and cracked centers were reduced by (1) adjusting the die, (2) using grids behind the die, (3) controlling the drop from the die to the cutting table, (4) adjusting the tilt of the cutting table, and (5) stacking the brick during drying. The specific gravity was increased as much as 3.3% by using improved methods of setting the brick in saggers.
MEASUREMENT OF ENAMEL‐SLIP CONSISTENCY BY MEANS OF THE BROOKFIELD VISCOSIMETER*
Authors: Oliver Evan M.
Published: June 2006

Abstract

An instrument commonly employed to measure the viscosity of truly viscous liquids was tested to determine its applicability for evaluating consistencies of enamel slips which are solid suspensions in a water medium. Within wide limits of specific gravity differences and variations in set resulting from electrolyte additions, the Brookfield vis‐cosimeter afforded comparable information with the pick‐up and slump tests employed as references.
A NEW METHOD FOR STUDYING FRACTURES OF PORCELAIN ENAMELED SPECIMENS*
Authors: Petersen F. A. , Jones Rodney A. , Allen A. W.
Published: June 2006

Abstract

A process is described which locates microscopic cracks in an enamel layer. This method shows great promise in the study of different types of fractures of porcelain enameled specimens. An analysis of the stress conditions in the enamel‐iron‐enamel system before, during, and after thermal shock is also included.
VISCOSITY STUDIES OF SYSTEM CaO‐MgO‐Al2O3‐SiO2: II, CaO‐Al2O3‐SiO2*
Authors: Machin J. S. , Yee Tin Boo
Published: June 2006

Abstract

Viscosity data are presented covering those compositions in the CaO‐Al2O3‐SiO2 system which are liquid at 1500°C. The pattern of isokoms on the CaO‐Al2O3‐SiO2 face of the compositional tetrahedron which represents the CaO‐MgO‐Al2O3‐SiO2 system is a system of lines which roughly parallel the lines along which the lime content is constant. There are, however, considerable deviations from this parallelism in regions of very low and very high alumina content.
SOME ENERGY RELATIONS IN THE SYSTEMS PbO‐B2O3 AND PbO‐SiO2*
Authors: Shartsis L. , Newman E. S.
Published: June 2006

Abstract

Heats of solution of a series of glasses in the system PbO‐B2O3 were measured in 2 N nitric acid with a simple vacuum‐bottle calorimeter. Heats of solution of a series of glasses in the system PbO‐SiO2 ranging in composition from 6 to 35% of SiO2 were measured in a mixture of HF and 2.5 N nitric acid with an electrically calibrated isothermal jacket calorimeter. From these data and heats of fusion available in the literature, calculations were made of the heats of reaction of the component oxides in either amorphous or crystalline states in forming glasses in these systems.
EFFECT OF SIZE AND SHAPE OF TITANIUM OXIDE CRYSTALS ON SPECTROPHOTOMETRIC PROPERTIES OF TITANIUM‐BEARING PORCELAIN ENAMELS*
Authors: Friedberg A. L. , Fischer R. B. , Petersenr F. A.
Published: June 2006

Abstract

Color changes of three titanium enamels given varied firing treatment were investigated. The size and shape of titanium oxide particles were studied with the electron microscope, the relative amounts of anatase and rutile were determined from X‐ray analyses, and spectrophotometric curves of the fired panels were made.

Electron micrographs showed that rutile particles recrystallized as needles or “sticks,” whereas anatase appeared as ill‐defined, irregularly shaped, rounded particles. With increasing firing temperature or firing time (1) rutile particles showed a greater increase in size than anatase particles, (2) the amount (by weight or volume) of anatase crystals decreased and the amount of rutile crystals increased, and (3) a color change from blue‐white to cream‐white was observed.

The change in color seemed to be related to the scattering of blue light by small particles at lower temperatures or shorter periods of firing. As the size of opacifying particles increased, the scattering of blue light decreased, and the characteristic absorption of visible light in the shorter wave lengths was more apparent. In enamels containing both anatase and rutile, the smaller anatase crystals were predominant at lower and the larger rutile crystals at higher temperatures, so that sharp changes of color were observed as the firing temperature was increased.
Observations on the Thermal Expansion of Crystalline and Glassy Substances
Authors: HUMMEL F. A.
Published: June 2006

The importance of the reversible thermal expansion of inorganic substances is recognized by metallurgists, glass technologists, and ceramists who deal with manufactured products that are subjected to temperature cycles in service. The temperature interval involved may be small, as in dental porcelain, or large, as in open‐hearth refractory brick. In spite of the major influence of this property on the practical service life of industrial products, very few broad principles have been advanced regarding the effect of crystal structure on the reversible thermal expansion of pure compounds. In general, close‐packed crystalline structures of the sodium chloride or spinel type, which have simple geometrical arrangements, seem to have high expansions. Less‐symmetrical structures apparently have a lower expansion, for example, the moderately refractory materials zircon, beryl, beta‐spodumene, and willemite.
Some Observations on Reactions of Enamel and Iron
Authors: MILLER GRANT E. , SWEO B. J.
Published: June 2006

Gas evolution was observed during the course of heating mixtures of powdered iron and finely divided enamel frits. The specific gravity of the resulting mass was taken as an index of the degree of gas evolution. Gas‐evolution data were obtained as a function of time of heating, temperature employed, material addition, and type of frit in the mixture. Tests with metals other than iron were also conducted.
Nepheline Syenite‐Talc Mixtures as a Flux in Low‐Ternperature Vitrified Bodies
Authors: LYNCH E. D. , ALLEN A. W.
Published: June 2006

A study was made of the use of nepheline syenite‐talc combinations as a flux for producing vitrified bodies at low temperatures. It was found that a mixture of 85% nepheline syenite and 15% talc had a lower deformation temperature than either of these materials alone, indicating a eutectic in the system. Bodies were compounded by adding nepheline syenite and talc, in the ratio found to be the most fusible, to clays and flint. Bodies were developed that had less than 0.3% absorption in the firing range cone 02 to cone 2. These bodies had good color. Their modulus of rupture values ranged from 7000 to 10,000 lb. per sq. in.
Flame Fusion Synthesis of Mullite Single Crystals
Authors: BAUER W. H. , GORDON I. , MOORE C. H.
Published: June 2006

In conjunction with the Office of Naval Research project on tourmaline synthesis, an incongruently melting silicate, mullite, has been grown by the flame fusion process. The equipment and the feed materials are described. X‐ray and petro‐graphic evidence that identifies the boule as a single crystal of mullite is given; no other crystalline phase or glass is present. The results and the possibilities of the growth of other silicates by flame fusion are discussed. This synthesis indicates that the flame fusion technique is feasible for the study of and the possible single‐crystal growth of certain anhydrous silicates.