ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1948.tb14282.x

出版商:Blackwell Publishing Ltd    

年代:1948

数据来源: WILEY

摘要:

AbstractRefractory ceramic base coatings were formulated and developed for application to ingot iron, low‐carbon steel, and alloy metals. Mill additions to increase the effectiveness of the coatings produced from various frit glasses were studied. Diaspore proved to be the most desirable of the materials considered. The formulation of special frit glasses was undertaken to further increase the refractoriness and heat‐resistant properties of ceramic coatings. The effects of changes in the base composition and the inclusion of various refractory materials was investigated. Tests for the evaluation of the coatings are listed with a summary of the results obtained. Metal preparation and procedures are described. Sandblasting is the recommended method of preparing metals for coating. Results of service tests are discussed. The important part that ceramics can play in aeronautics is pointed

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1948.tb14283.x

出版商:Blackwell Publishing Ltd    

年代:1948

数据来源: WILEY

摘要:

AbstractThe most important characteristic of a piece of glassware such as a bottle or a jar is its serviceability, that is, the amount of use which can be obtained from it. In the case of glassware which is subject to repeated re‐use, this serviceability may be thought of in terms of length of life, measured either by months or years, if the service is uniform, or measured by the number of trips successfully undergone if it is not.The termination of the serviceability of such glassware is due to breakage, and breakage in turn is, in the vast majority of cases, due to impact. But a piece of glassware may survive many severe impacts, only to succumb to a comparatively minor one. Impact alone is not the whole story. Glassware must be prepared for breakage by undergoing a process of use and abuse during which the surface is scratched, abraded, and otherwise damaged and thus rendered vulnerable to the final stroke.In the present paper the assumption is made that in nearly all cases breakage involves two separate and independent processes, the “vulnerating” process and the final impact. On this assumption a mathematical treatment is evolved which yields a mortality curve showing the relation between the rate of breakage and the service age of a given installation of glassware. This curve has been found to represent quite accurately the results of a service test on glass tumblers conducted in an actual restaurant.Impact strength, as determined by laboratory tests, declines with service age in a way consistent with the above assumption. These strength data, furthermore, may be correlated with the results of the service test.Additional data are being secured from other service tests now in pro

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1948.tb14284.x

出版商:Blackwell Publishing Ltd    

年代:1948

数据来源: WILEY

摘要:

AbstractBy means of X‐ray crystallographic studies it has been proved that fused corundum abrasives are mainly α‐Al2O3or a solid solution of 10.6 mol.% Ti2O3in alumina. In addition, the following crystalline impurities forming a matrix have been identified: a calcium titano‐aluminate with variable composition CaO.[6(Al, Ti)2O3], spinel (MgO.‐Al2O3), Na2O.11Al2O3, quartz, rutile, and an iron‐silicon‐titanium alloy.Knoop microhardness numbers and dimensions of the unit cell of the corundum lattice have been determined and correlated with the chemical composition of various corundum abrasives. It has been found that the formation of a solid solution of Ti2O3in Al2O3is followed by a decrease of the microhardness of the corundum phase from about 2100 for the pure alumina to about 1940 for the solid solution. The latter has been found in all commercial corundum abrasives containing more than 1.5% TiO2, the former in all white titanium‐free samples. In making fused corundum blocks in large experimental electrical arc furnaces from various low‐grade bauxites and coke, the corundum obtained contained only about 1% TiO2, minute changes in the furnacing effecting the formation of the pure and hard corundum or the softe

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1948.tb14285.x

出版商:Blackwell Publishing Ltd    

年代:1948

数据来源: WILEY