AN INVESTIGATION OF THE ALUMINUM–OXYGEN–CARBON SYSTEM

1963 ◽  
Vol 41 (3) ◽  
pp. 671-683 ◽  
Author(s):  
J. H. Cox ◽  
L. M. Pidgeon
Keyword(s):  
Aluminum Carbide ◽  
Direct Reaction ◽  
Free Energies ◽  
Equilibrium Pressure ◽  
Analysis Technique ◽  
Differential Thermal Analysis Technique ◽  
Calculated Equilibrium ◽  
Direct Solid ◽  
Reduced Pressures ◽  
Carbon System

A differential thermal analysis technique was used to study the carbothermic reduction of aluminum oxide at reduced pressures in the temperature range 1700–2200 °K. The reduction was found to proceed through the intermediate oxycarbide Al4O4C, identified by previous workers, to the aluminum carbide. The Al4O4C and another oxycarbide, Al2OC, were formed by a direct solid–solid reaction, rather than by formation of a gaseous aluminum suboxide and subsequent reaction with carbon as has been postulated.The carbon monoxide pressures over the following reactions were measured:[Formula: see text]Heats and free energies of reaction were found and standard heats and free energies of formation were calculated for Al2OC, Al4O4C, and Al4C3. The values for Al4C3 agreed with previously published results.The direct reaction[Formula: see text]did not occur. To account for the aluminum produced at high temperatures, the reaction below was postulated:[Formula: see text]The calculated equilibrium pressure above this reaction agreed with experimental observations.

Oxidation Properties of ZrB2-20vol.%SiC-10vol.%BN Ceramic Composite at 1200°C

2010 ◽  
Vol 105-106 ◽  
pp. 165-167
Author(s):  
Gang Li ◽  
Wen Bo Han
Keyword(s):  
Ceramic Composite ◽  
Oxidation Mechanism ◽  
Ceramic Composites ◽  
Third Phase ◽  
Analysis Technique ◽  
Static Oxidation ◽  
Oxidation Properties ◽  
Hot Pressing Sintering ◽  
Differential Thermal Analysis Technique ◽  
Oxidation Behaviors

Dense ZrB2-20vol.%SiC-10vol.%BN (ZSB) ceramic composites by introducing BN as the third phase are fabricated through hot pressing sintering under inert gas protected. The static oxidation behavior of the ZrB2-SiC-BN ceramic composite at 1200°C in air is analyzed using differential thermal analysis technique, and the surface morphology of the composites after oxidation at 1200°C is examined using scanning electron microscopy along with energy dispersive spectroscopy. The microstructure change and oxidation behaviors of the ZrB2-SiC-BN ceramic composite are investigated. The effect of BN grain size is analyzed and the oxidation mechanism in ceramic composites is discussed correspondingly.

Growth Rate of Natural Rubber Crystallites

1966 ◽  
Vol 39 (2) ◽  
pp. 206-210 ◽  
Author(s):  
R. E. Hammett ◽  
R. E. Wingard ◽  
J. E. Land
Keyword(s):  
Thermal Analysis ◽  
Growth Rate ◽  
Differential Thermal Analysis ◽  
Natural Rubber ◽  
Degree Of Crystallinity ◽  
Melting Range ◽  
Analysis Technique ◽  
Heat Effects ◽  
Differential Thermal Analysis Technique ◽  
The Degree Of Crystallinity

Abstract The melting range and growth rate curves for natural rubber crystallites have been studied by the differential thermal analysis technique. The results obtained compare favorably with the growth rate curves obtained by dilatometric techniques. The use of differential thermal analysis revealed details of the crystallite melting which were not apparent when the dilatometer was used; however, no quantitative data on heat effects or the degree of crystallinity were calculated.

Liquidus projection of the ternary Ag–Sn–Ni system

2004 ◽  
Vol 19 (8) ◽  
pp. 2262-2267 ◽  
Author(s):  
Sinn-wen Chen ◽  
Hsiu-feng Hsu ◽  
Chih-wei Lin
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Ternary System ◽  
Liquidus Projection ◽  
Thermal Analysis Technique ◽  
Primary Solidification Phase ◽  
Ni Alloys ◽  
Analysis Technique ◽  
Differential Thermal Analysis Technique ◽  
Rich Side

The liquidus projection of the ternary Sn–Ag–Ni system at the Sn-rich side was determined experimentally. No ternary compound was found, and the ζ–Ag4Sn, Ag3Sn, and Sn existed as the primary solidification phases only in very small compositional portions of the ternary Sn–Ag–Ni system. In more than half of the compositional regime of the ternary system, the Ni3Sn2 phase was the primary solidification phase. The differential thermal analysis technique was used to determine the reaction temperatures and solidification sequences of various Sn-rich Sn–Ag–Ni alloys. Three invariant reactions were found: L = Sn + Ni3Sn4 + Ag3Sn, L + ζ–Ag4Sn = Ni3Sn4 + Ag3Sn and L + Ni3Sn2 = ζ–Ag4Sn + Ni3Sn4. Their reaction temperatures have been determined to be 219, 488, and 516.5 °C, respectively.

Studies on Water in the Hydration Chamber of a Modified Electron Microscope

1970 ◽  
Vol 28 ◽  
pp. 544-545
Author(s):  
R. C. Moretz ◽  
G. G. Hausner ◽  
D. F. Parsons
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Electron Microscope ◽  
Steady State ◽  
Room Temperature ◽  
Small Mass ◽  
Equilibrium Pressure ◽  
Biological Objects ◽  
Mechanical Pump ◽  
Differential Pumping

Use of the electron microscope to examine wet objects is possible due to the small mass thickness of the equilibrium pressure of water vapor at room temperature. Previous attempts to examine hydrated biological objects and water itself used a chamber consisting of two small apertures sealed by two thin films. Extensive work in our laboratory showed that such films have an 80% failure rate when wet. Using the principle of differential pumping of the microscope column, we can use open apertures in place of thin film windows.Fig. 1 shows the modified Siemens la specimen chamber with the connections to the water supply and the auxiliary pumping station. A mechanical pump is connected to the vapor supply via a 100μ aperture to maintain steady-state conditions.

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