ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1957.tb12539_ca.x

出版商:Blackwell Publishing Ltd    

年代:1957

数据来源: WILEY

摘要:

Results are presented of a study of phase equilibria among crystalline and liquid phases in the quaternary system CaO–MgO‐Al2O3–SiO2at Al2O3contents greater than 35%. Equilibrium diagrams shown are for the five triangular joins CaAl2Si2O3‐Ca2Al2SiO7‐MgAl2O4, Ca2Al2SiO7‐MgAl2O4‐Al2O3, CaAl2Si2O8‐MgO‐Al2O3, CaAl2Si2O8‐Mg2SiO4‐MgAl2O4, and CaAl2Si2O8‐MgO‐Mg2SiO4. The composition and nature of the four quaternary peritectic points and the relationships of univariant lines and primary ph

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1957.tb12540.x

出版商:Blackwell Publishing Ltd    

年代:1957

数据来源: WILEY

摘要:

Samarium oxide forms a ceramic of medium strength and density (6.0) when it is fired at 1300°C. When it is fired at 1500°C., its density is increased to 7.4 but it loses its stability toward boiling water. X‐ray data are given concerning the structure of the oxide as received and at 1300°C. and of the reaction product of Sm203 with water. Gadolinium oxide forms a ceramic of somewhat higher density (7.0) at 1300° than does Sm2O3; at 1500°C. its density is slightly higher (7.6) whereas its stability toward water is unchanged. Data concerning both oxides include density, shrinkage, moduli of elasticity and of rupture, linear thermal expansion, differential thermal analysis, and specific heat as well as X‐ray data. Results are given of a brief survey of the reaction products obtained when Sm2O3and Gd2O3are heated at 1500°C. in equimolecular quantities with Al2O3, BaO, CaO, CdO, Fe2O3, HfO2, MgO, SO2, SrO, ThO2, and ZrO2. X‐ray data for the following rare‐earth oxides as received and after calcination at 1400°C. are given: ceria, praseodymia, neodymia, europia, dysprosia, holmia, erbia, thulia

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1957.tb12541.x

出版商:Blackwell Publishing Ltd    

年代:1957

数据来源: WILEY

摘要:

The strength properties of sintered alumina rods, as determined by modulus of rupture experiments, were measured for the purpose of finding the influence of grain size on strength. Sintering temperatures below and above the recrystallization temperature region were utilized in the fabrication of sintered alumina rods so that a wide variation of grain sizes could be tested. Porosity, measured as bulk density, had the largest influence on the moduli of rupture. No prominent change in strength could be observed as a result of recrystallization, but a minor decrease in strength could be attributed to an increase in void size or an increase in grain size.

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1957.tb12542.x

出版商:Blackwell Publishing Ltd    

年代:1957

数据来源: WILEY

摘要:

Auxiliary flux additives to milled enamels for aluminum must serve (a) as an inhibitor or alkali “buffer” in enamel‐metal reactions and (b) as a flux to aid rapid enamel fusion during the early stages of firing. Raw and fritted mixtures were varied in two milled aluminum enamels. The effects of these mixtures on the physical properties, drying and firing characteristics, and water spalling resistance are tabulated. Results indicate that the proper balance between alkali, B2O3, and SiO2functions best to meet these require

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1957.tb12543.x

出版商:Blackwell Publishing Ltd    

年代:1957

数据来源: WILEY

摘要:

A moisture‐condensation technique previously described was utilized in a study of the effect of polishing on fracture patterns in glass surfaces. The experiments show that the apparent controversy concerning the polishing out or “bridging over” of surface fractures may be resolved on the basis of crack dimensions. If the fracture width is less than 1/4 λ, it may be sealed over by polishing, even though the depth may be 1 mm. or more. A modified condensation chamber was devised to show in detail the effect of aging and fracture growth in polished su

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1957.tb12544.x

出版商:Blackwell Publishing Ltd    

年代:1957

数据来源: WILEY