ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1950.tb13463.x

出版商:Blackwell Publishing Ltd    

年代:1950

数据来源: WILEY

摘要:

The term “Parian china” is defined and the various types are described. Data are presented showing the range of time‐temperature schedules by which certain types of this ware may be matured to produce desired vitrification and surface tex

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1950.tb13464.x

出版商:Blackwell Publishing Ltd    

年代:1950

数据来源: WILEY

摘要:

The progressive attack on polished glass surfaces caused by exposure to high humidity conditions was studied with photomicrographs and by measuring the visible–light transmissions. Carefully polished specimens of five commercial glasses representing a wide range of chemical durability were exposed to relative humidities of 95, 73, and 57% at 90°C. for a total of 1296 hours. Photomicrographs taken at frequent intervals show the degree of surface alteration as a function of time and humidity and furnish some basis for characterizing the course of weathering. For some glasses, the transmission losses did not correlate simply with the amount of visible attack; gains in transmission were noted frequently as the attack progressed. One glass in particular exhibited a general trapsmission gain of 1% after 24 hours of weathering and maintained this gain throughout the tests. Surface films produced on the least resistant glasses caused greater transmission loss in the blue region of the visible spectrum than in the red. Following a dilute‐acid wash, transmissions approached, or in some cases exceeded, values characteristic of the original polished condi

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1950.tb13465.x

出版商:Blackwell Publishing Ltd    

年代:1950

数据来源: WILEY

摘要:

An extensive composition study of titania enamels and their properties is described. The compositions investigated contained only six constituents, namely, Na2O, K2O, SiO2, B2O3, TiO2, and F2. Systematically and over a wide range, the contents of SiO2, B2O3, TiO2, and alkali were varied. One hundred enamels in all were made and the resulting properties were determined. Properties noted included flow, expansion, color, percentage of anatase, gloss, reflectance, and acid resistance at various firing temperatures.Enamel Y12, representing a small area in this large composition field, exhibited the properties requisite for a good hollow–ware white cover–coat enamel. Compared with previously studied titania enamels, this enamel is “softer”; i.e., it fires at lower temperatures, has the desired higher flow and expansion, yet still possesses the required properties of color stability, reflectance, gloss, acid resistance, and work

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1950.tb13466.x

出版商:Blackwell Publishing Ltd    

年代:1950

数据来源: WILEY

摘要:

An electric resistance furnace is described that is capable of operating at temperatures up to 3770 °F. (2075°C.)in vucuoor in hydrogen or noble‐gas atmospheres. Problems of outgassing and atmosphere contamination by furnace materials are largely circumvented by eliminating insulat

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1950.tb13467.x

出版商:Blackwell Publishing Ltd    

年代:1950

数据来源: WILEY

摘要:

A method of sintering carbides has been evolved that permits fabrication of dense, strong pieces having accurate dimensions and containing no residual binder metal. To aid in sintering, a small percentage of a binder such as cobalt or nickel, or their oxides, is added, but this is later removed by volatilization during the high‐temperature vacuum sintering operation. The method has been applied to tungsten carbide, tantalum carbide, and columbium carbide. The good mechanical properties of the products are cited as evidence for the carbide‐skeleton theory advanced to account for the high strength of cemented carbi

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1950.tb13468.x

出版商:Blackwell Publishing Ltd    

年代:1950

数据来源: WILEY