bluuebunny/crossref_metadata_2025_split huggingface dataset:
SOLID REACTIONS AT 1000° TO 1200°C BETWEEN MgO OR BeO AND Ni, Fe, Cr, Mn, AND THEIR OXIDES*
Authors: Navias Louis 
Published: April 2007

AbstractThe elements, Ni, Fe, Cr, and Mn, and their oxides, NiO, Fe2O3, Cr2O3, and MnO2, in a finely divided state, were brought into contact with granular fused MgO in loose form and in pressed disks and also into contact with slabs of high‐fired MgO and BeO. The maximum temperatures reached were 1000°C, 1100°C, and 1200°C in air firings. The degree of reaction was noted by the extent of discoloration of the MgO and BeO near the contact material. Ni showed the least reactivity, Fe and Cr came next, and Mn showed the most reaction. The oxides gave the same order of reactivity, NiO, Fe2O3 and Cr2O3, and MnO2, the most. The elements in oxidizing caused more reaction than their oxides in all cases. There was less reaction with BeO than with MgO for corresponding contact material.Firings were also made with these elements and oxides in contact: with pressed disks of fused MgO but in a hydrogen atmosphere. Ni and Fe showed no reaction; Cr, a very slight reaction; and Mn, slightly more reaction. NiO and Fe2O3 were reduced to their elements without reaction, whereas Cr2O3 did not reduce and gave no reaction. MnO2 became semi‐sintered and gave a very slight reaction.Other experiments were made by passing air or N2, dry or through water, into mixtures of granular fused MgO and Mn, MnO2, or Cr, respectively. At 1200°C, reaction was greatest with moist air.
STRESS RELEASE IN GLASS A PHENOMENON INVOLVING VISCOSITY AS A VARIABLE WITH TIME*
Authors: Lillie Howard R. 
Published: April 2007

ABSTRACTThis paper contains a discussion of the well‐known Adams and Williamson annealing law which makes the rate of release of stress in glass proportional to the second power of the stress and points out certain fundamental objections to such a law. A new expression free from these objections and taking into consideration the change of viscosity with time at constant temperature is given as ‐df/dt= Mfφ, where M is a modulus and φ the instantaneous fluidity. Experiments made with an ordinary lime glass show that this law holds for the release of mechanical stresses imposed on strain‐free glass as well as for the release of thermal stresses in chilled samples. The value of M found for these two types of stress at two different temperatures is 5.9 (±0.5) × 1010 dynes/cm.2.
EFFECT OF MILL PRACTICE AND MILL ADDITIONS ON THE OPACITY OF ENAMELS*
Authors: Bryant G. L. , Porter F. R. 
Published: April 2007

ABSTRACTThe results are presented on work done to increase the opacity of enamels by mill practice and mill additions, such as milling to abnormal fineness, addition of opacifiers at the end of the milling period, the effect of the addition of feldspar, and the effect of different types of clays.
INFLUENCE OF GLAZE COMPOSITION ON THE MECHANICAL STRENGTH OF ELECTRICAL PORCELAIN*
Authors: Thiess L. E. 
Published: April 2007

AbstractThe influence of the glaze composition upon glaze fit and mechanical strength has been studied on a series of commercial and twelve experimental glazes. The latter have a RO constant of 0.3 K2O, 0.7 CaO, 0.4 to 0.7 Al2O3, and 2.4 to 5.6 SiO2. The coefficient of thermal expansion was determined by calculation. Glazes high in fluxes (feldspar and whiting) appear to be unfavorable to high strength and good glaze fit.
RECENT REVISIONS OF HIGH TEMPERATURES*
Authors: Wensel H. T. 
Published: April 2007

AbstractThis paper points out that, to convert temperature values recorded in the literature to the present International Temperature Scale, a correction must be applied which is calculated from the constants that define the particular scale upon which the recorded values are expressed. Applying the same corrections to all previous scales leads, in many cases, to values which depart from the present scale more than the values actually recorded.Examples are given showing the proper method of converting temperature values based on Wien's Law to the International Scale.
EFFECT OF MILL ADDITIONS ON THE THERMAL EXPANSION OF SHEET‐IRON GROUND‐COAT ENAMELS*
Authors: Fellows R. L. , Howe E. E. 
Published: April 2007

AbstractSince the effect on thermal expansion of clay, feldspar, and silica, when introduced as mill additions to a sheet‐iron ground‐coat enamel, has not hitherto been clearly shown, thermal‐expansion studies were made on a two‐frit ground‐coat enamel for sheet iron, varying the amounts of clay, feldspar, and silica within reasonable limits of mill additions.It is common practice to use a combination of a hard and a soft frit ground coat to give greater flexibility in firing and operation, but it is not known whether the two frits form a single glass upon firing to give an expansion dependent upon the relative amounts of each frit present. Thermal‐expansion tests, therefore, were also made on enamels containing varying proportions of high‐ and low‐expansion frits.Results were obtained by the use of the interferometer, and the rod method of making specimens as used by Andrews and Smith1 was compared to the plate method described in this paper. Through the use of these two methods of preparing the samples, a comparison of the relative solubility of the mill additions in the ground‐coat frit was secured.
X‐RAY STUDIES OF CRYSTALLINE SUBSTANCES IN GLASSES*
Authors: Hicks Victor 
Published: April 2007

AbstractX‐ray diffraction methods may be used not only to determine the atomic arrangements in the vitreous state, but also to detect the substances responsible for color, opalescence, or opacity, and to establish the existence of selective molecular orientation in surface films. By such methods it has been shown that a solid solution of cadmium sulfide and cadmium selenide is responsible for the color of certain ruby glasses. Similarly, the opacity of certain annealed soda‐lime‐silica‐fluoride opal glasses has been attributed either to quartz or to cristobalite, depending on the thermal history; if alumina is added to these glasses, tridymite appears after a similar heat treatment. Chromic oxide has been found to crystallize from certain enamel glasses but not cobalto‐cobaltic oxide. No detectable selective molecular orientation occurs in the surface layers of the resinous films used in certain safety glasses.
I. THE MICROBIOLOGY OF AGING CLAYS*
Authors: Glick Dudley P. 
Published: April 2007

AbstractThe literature pertaining to microorganisms in clay and the aging of clay is reviewed. Preliminary to attempting to determine the effect of microörganisms upon the aging of clay, six clay bodies have been examined and the numbers and kinds of microorganisms have been determined. The numbers of bacteria found, the variety of species, and then‐growth upon a medium prepared from an extract of ball clay are indicative of their activity. The bacteria identified are typical soil and water organisms. A method has been devised for the examination of the interior of lumps of native clay. One such clay gave no evidence of harboring living organisms beneath its surface, whereas the surface was highly contaminated, probably from external sources.
PHYSICAL‐CHEMICAL REACTIONS IN FIRING WHITEWARE*
Authors: McVay T. N. 
Published: April 2007

AbstractThe present knowledge concerning reactions which take place during the heat treatment of clay, feldspar, and silica is discussed as well as the relations of these three to the ternary system K2O‐Al2O3‐SiO2. The manner of growth of mullite crystals in feldspar has been studied. Additional experimental data as evidenced by the thermal‐expansion curves of day‐feldspar and clay‐silica mixtures previously fired at high temperatures are presented.
III. THE EFFECTS OF VARIOUS TREATMENTS UPON THE AGING OF A CERAMIC BODY*
Authors: Glick Dudley P. 
Published: April 2007

AbstractA preliminary study of the effects of various substances upon the aging of a ceramic body in the sterile and in the natural states is presented. The influence of each treatment on the growth of microörganisms is noted. In the case of tannic acid, the effect upon the physical properties of the body in the absence of microbial activity was especially pronounced. There is presented what is believed to be the first instance of the measurement of oxidation‐reduction potential in a ceramic material. Oxidation‐reduction potential is suggested as an index to microbiological activity in aging clay.
FRIT SOLUBILITY: I, COMPARISON OF METHODS OF DETERMINATION AND RELATION OF SOLUBLE SALTS TO ENAMEL SLIP CONSISTENCY*
Authors: McIntyre G. H. , Bevis R. E. 
Published: April 2007

AbstractFrit solubilities were determined (1) by extraction in a standard Soxhlet extraction apparatus and (2) by milling in the usual manner. Titrations were made by the potentiometrie method, using the glass electrode, and compared to the usual indicator method.The relationship between these soluble portions of the frit and enamel‐slip consistency was studied.
THE ANALYSIS OF FELDSPAR* Method for Determination of Normalities of Potassium Bromate and Sodium Thiosulfate in the Knowles‐Redmond Volumetric Procedure for the Determination of Alumina
Authors: Koenig K. W. 
Published: April 2007

AbstractA method is described whereby the normalities of the oxidation‐reduction solutions used in the volumetric determination of alumina in feldspar, after separation as quinolate, are determined without the use of standards other than those which enter the reaction in the routine procedure.
A COMPARISON OF THE THERMAL EXPANSION OF USED SILICA BRICK FROM AN INSULATED AND AN UNINSULATED OPEN‐HEARTH FURNACE ROOF*
Authors: Pierce R. H. H. , Austin J. B. 
Published: April 2007

AbstractMeasurements of the linear thermal expansion of different zones in the used silica roof brick whose composition and structure have been described by Harvey show that along the length of the brick there are two abrupt changes in expansion. The first, whose existencè was predicted by Harvey and by Miller, coincides with the limit of penetration of iron oxide and arises from the fact that in the presence of iron oxide the silica, originally present as cristobalite, has been largely converted to tridymite, which has a different expansion. The limit of penetration of iron oxide is taken as that level at which the average temperature is 1100°C (2010°F), the temperature of the ternary eutectic in the system CaO‐FeO‐SiO2; consequently, the abrupt change in expansion, and therefore a zone of weakness, is to be expected after equilibrium has been established in any open‐hearth roof brick whose cold end is below 1100°C (2010°F). The second change, which is also due to a discontinuity in the distribution of cristobalite, occurs at that level in the brick at which the average temperature was 1470°C (2080°F), the lower limit of the stable range for cristobalite. In each case the change in expansion arises directly from a difference in the length‐change at the cristobalite inversion, which takes place at approximately 250°C (480°F), so that failure or spalling is most likely to occur when the roof is cooled below or heated through this temperature. The expansion data also show that the inversion temperature of cristobalite increases regularly with the temperature at which it was formed or at which it was brought to equilibrium.The data obtained enable the determination of the average distribution of tempera ture through the brick in service, which, combined with existing data on thermal conductivity of silica brick, permits an estimation of the mean thermal conductivity of that part of the brick into which iron oxide has penetrated. This conductivity is greater than that of the rest of the brick and has a negative temperature coefficient in contrast to the positive coefficient for the unaltered part.
NOTE ON A NEW DRY‐PRESS DE‐AIRING DEVICE*
Authors: Curtis C. E. 
Published: April 2007

AbstractThree general methods for de‐airing a dry press are (1) double‐pressing, (2) use of an easily condensable, gas, and (3) direct de‐airing. In an investigation of the latter it was found best to evacuate the mold box through holes drilled in the die pads. To keep the holes free of clay, a device called a “cleaning grid” was developed. A description of the construction and operation of an installation of this device is given.
MULLITE DEVELOPMENT IN SUPER‐DUTY FIRECLAY BRICK*
Authors: Harvey Fred A. , Birch Raymond E. 
Published: April 2007

AbstractSpecimens of super‐fireclay brick, fired to cones 11, 13, and 18, were compared to determine the amount of mullite developed. X‐ray diffraction patterns of the three specimens compared with standard samples containing 40, 50, and 60% mullite indicated that all three specimens contained approximately 50% mullite. Petrographic examination showed distinct mullite crystals in the specimen fired to cone 18, while no mullite crystals could be identified in the specimen fired to cone 11. It is concluded that firing to higher temperatures than cone 11 increases the size of the mullite crystals but probably not the total amount of mullite present.
THE MODULUS OF ELASTICITY OF GLASS*: I Preliminary Studies: (a) Effect of Thermal History; (b) Effect of Temperature Change
Authors: Stong Guy E. 
Published: April 2007

AbstractAn apparatus has been set up with which the modulus of elasticity of glass may be determined with a probable error of ±0.2%. Results are presented showing that the modulus of this glass varies over R range of 7%, depending upon its previous thermal history, the modulus being higher for low‐temperature heat treatments. Determinations of the modulus have been made up to 450°C upon samples having different thermal histories. It has been found that the modulus decreases regularly, the rate of change increasing with rising temperature.
BALANCING HOLLOW‐WARE DIES WITHOUT THE USE OF DRAGS THEREBY INCREASING CAPACITY*
Authors: Longenecker H. L. 
Published: April 2007

AbstractTo produce ware which will not crack in the drier, tile must be extruded from a die at a uniform velocity across the die. It is sometimes difficult to make the clay fill the corners of a large die. In common practice, a die is balanced by placing drags on the rear ends of the core post at the section of the die which runs fast, retarding the clay flow at that point sufficiently to equalize the flow across the die. The difficulty in filling the corners is overcome by making deep semicircular gouges in the die behind the corners.It has been found better practice to speed the slow parts of the die by altering the taper of cores, shifting the cores sidewise to increase the web thickness at the slow sections, and thinning the web thickness at the fast sections. Gouging the corners is a form of dragging which is overcome by using better design.Experimental data, drawings, photographs, instructions for die building and balancing, and proper taper of dies and cores are given. A die balanced without drags increases the tonnage per hour and reduces the power requirements.
THE SCRATCH‐RESISTING POWER OF GLASS AND ITS MEASUREMENT*
Authors: Bailey James 
Published: April 2007

AbstractMethods used by previous investigators yield valuable data but do not give the order of hardness of different glasses, nor do the results agree in many instances with usual conceptions of relative hardness. A study of the problem had indicated that the scratch resistance of a glass surface depends upon factors other than the mechanical strength of the body of the glass. An examination of used glass articles showed that the scratches could be divided roughly into two classes: surface abrasions and scratches produced by crushing the surface. The ability of one material to scratch another depends upon the velocity of motion and upon the refractoriness of the material forming the point.Preliminary work has shown that a test for the scratch‐resisting power of a glass surface should test the surface as it exists upon the article. The conditions causing the initial rupture of the surface should be used as a measure of the scratch‐resisting power of the particular surface.The method adopted for testing the surface consisted of rolling a 1/8‐inch diameter steel ball over the surface in such a manner that the pressure increased as the ball rolled along. The pressure at which the first conchoidal breaks occurred was used as a measure of the hardness.Natural surfaces such as those of drawn window glass vary in hardness. Fused silica glass has a value of 10 to 12 pounds, common window glass has values of about 25 pounds, while some glass with a high alumina content has much higher values. Ground and polished surfaces are softer than fire‐polished surfaces on the same glass, and strained glass has a harder surface than the same glass in the annealed state.Illustrations of various types of new scratches, weathering effects along scratches, weathering effects in cracks and fractures, and a series of the ball tracks left in a glass surface by the tests are shown.
MECHANICS OF ENAMEL ADHERENCE: XIII, A REVIEW OF THE THEORETICAL EXPLANATIONS FOR FORMATION OF METAL PARTICLES IN “COBALT” GROUND COATS AND SOME PERTINENT EXPERIMENTS*
Authors: King R. M. 
Published: April 2007

AbstractLuther's rule has been suggested to explain the action of FeO, or its solid solutions with oxygen, in forming both Fe and Fe3O4. The theories of Ebell and others have also been reviewed. An X‐ray analysis of previously fired “cobalt” ground coat and a photomicrograph of an iron‐oxide enamel are given.
THE EFFECT OF ZrO2, AND TiO2 UPON THE RESISTANCE TO CRAZING OF A TYPICAL GLAZE FOR SEMIVITREOUS DINNERWARE*
Authors: Hepplewhite J. W. 
Published: April 2007

AbstractThe results of additions of ZrO2 and TiO2 to a typical glaze for semivitreous dinner‐ware are given with reference to the resistance to crazing, color, and texture of the resulting glazes.
ADHESION OF ENAMEL TO STEEL PRODUCED BY THE ELECTRODEPOSITION OF Mo(OH)3 ON THE STEEL*
Authors: Amberg C. R , Prior H. D. , Richmond J. C. 
Published: April 2007

AbstractIt has been found that the deposit of Mo(OH)3, produced when steel is made the cathode in a solution of ammonium molybdate, will cause a white enamel to adhere to steel. A theory is advanced, as a possible explanation, that the deposited coating prevents the formation of excess iron oxide which would weaken the enamel‐iron bond.
DE‐AIRING IN AN ORDINARY PUG MILL*
Authors: Stettinius Kenneth 
Published: April 2007

AbstractIn the top of the pug mill, in the region where the relatively air‐free press cakes are being churned and compacted, carbonic acid gas is substituted by displacement for the small amount of air which usually becomes entrapped. Visible gas blebs in the pug are eliminated or minimized, drying losses are greatly reduced, and the integrity of the product is improved. Methods of testing, visual and quantitative, are described to develop and indicate the presence of gases in the pugged clay. The results are illustrated.
TALC IN WHITEWARE*
Authors: Geller R. F. , Creamer A. S. 
Published: April 2007

AbstractThree talcs, representative of low, medium, and high CaO content, were used in preparing twenty‐four bodies which were heated at four temperatures. The products ranged from the highly porous earthenware type to porcelain, and test results indicate some possibilities and limitations which the white‐ware industry may expect of white‐ware bodies made with 14 to 40% talc.
THE USE OF SYENITES IN SEMIVITREOUS WARE: II, PLANT TRIALS*
Authors: Koenig C. J. 
Published: April 2007

AbstractFive‐inch plates indicating promising results were made from semivitreous bodies prepared (1) by introducing the syenite in reduced amounts and (2) by counteracting the greater fluxing action of the syenites as compared to feldspar by reducing the firing temperature. These plates passed autoclave, heat shock, impact, and chipping tests satisfactorily. When the plates embodying syenite failed after repeated tests, the failure was caused by dunting. In no case did crazing occur. Bodies in which equal parts of syenites were substituted for feldspar gave increased values for modulus of rupture and modulus of elasticity, but for the same degree of absorption the values fell within the same range. The syenite bodies showed less tendency to warpage than the feldspar body. The linear coefficient of expansion of the syenite bodies is greater than the corresponding feldspar body, and bodies combining feldspar and syenite are intermediate in this respect. Photomicrographs of body structure are included.
PROGRESS REPORT ON OCCURRENCE AND REFINING OF SOME OF THE TENNESSEE VALLEY PRIMARY KAOLINS, THEIR USE IN VITREOUS CERAMIC WHITEWARE BODIES, AND RESULTS OF EXPERIMENTS RUN TO DEVELOP A MODIFIED TYPE OF VITREOUS TRANSLUCENT DINNERWARE MADE FROM ALL‐AMERICAN MATERIALS*
Authors:   The Tennessee Valley Authority Ceramic Laboratory Staff
Published: April 2007

AbstractThis report is a collection of papers dealing with the occurrence and refining of primary North Carolina kaolins, their use in a vitreous china or porcelain‐type dinnerware body, some notes on casting and plastic forming of these bodies, and some preliminary results in determining the best firing schedules.The report also includes a statement of the purposes and aims of the laboratory and a description of the building and part of the equipment.
PART VI, PLASTIC FORMING OF VITREOUS BODIES OF TRUE PORCELAIN OR CHINA TYPE, USING AMERICAN KAOLINS AS PLASTIC CONSTITUENTS, WITH NOTES ON A NEW METHOD OF MANUFACTURING STRAIGHT FLAT WARE
Authors: Gould R. E. 
Published: April 2007

AbstractThe plastic forming of bodies previously described in Parts IV and V was easily and simply done by the usual semivitreous methods on all articles except flat ware which could be jiggered but which deformed in the firing process. A new method is described in which the plates are held rigid during the bisque‐firing process by braces made from the same body as the plates, supporting the points of the plates which tend to deform owing to the pull of gravity or internal stresses. One method of manufacturing these braces is described, which is apparently successful in most of its features. The method appears to be practical in that internal stresses induced during the manufacturing can be disregarded, thus making possible the use of simpler automatic forming machines and devices. Complete success has not yet been obtained, but failures have all been traceable to mechanical defects. Using this method requires a much higher degree of mechanical perfection than is common to the ceramic dinnerware industry but which is entirely within the bounds of practical possibility.
THE EFFECT OF ALUMINA ON THE SURFACE TENSION OF MOLTEN GLASS*
Authors: Parmelee By C. W. , Harman C. G. 
Published: April 2007

AbstractThe maximum bubble‐pressure method has been used to determine the surface tensions of molten glasses. The compositions of the glasses were those typical of certain types of commercial products. A brief summary of the theory and application of the method is presented. The surface tensions of the glasses studied were of the order of 300 dynes per centimeter and the temperature coefficients were — 0.017 dyne per centimeter per degree centigrade. It was found that A12O3 raised the surface tension of soda‐lime‐silica glass, the increase being almost linear between 2% Al2O3 and 8% Al2O3.
INTEGRAL EXPANSION OF VITREOUS ENAMELS BETWEEN THE SOFTENING POINT AND ROOM TEMPERATURE*
Authors: Rosbnbero J. H. , Langerman A. 
Published: April 2007

AbstractThe differential expansion of vitreous enamels and base metal is estimated from the mechanical properties of a closed ring of the sheet metal covered on the outside with enamel. An equation is derived relating the tangential static force necessary to overcome the stress in the ring to the coefficient of expansion and elastic properties of the enamel. The equation is reduced to linear form and a plot gives accurately (as–ae) ΔT, where as and ae are, respectively, the average coefficients of the steel and the enamel in the temperature interval, ΔT, between the softening point of the enamel and room temperature. The results by this method are in good agreement with those obtained by interferometer measurements.