Temperatures liquidus temperature

Liquidus Temperature. The Hquidus temperature determines the susceptibiUty of a glass to devitrification and therefore influences its forming limitations and often its heat-treating requirements. 

Silver-copper-palladium alloys with liquidus temperatures of 800-1 000°C have very low vapour pressures combined with good wetting and flow characteristics and are widely employed in vacuum work. They exhibit a lower tendency to stress corrosion than silver-copper, and do not form brittle alloys with other metals. 

Silver-palladium-manganese brazes possess excellent creep characteristics and have been developed for high-temperature applications involving the use of cobalt or nickel-based alloys, heat-resistant steels, molybdenum and tungsten. Their liquidus temperatures lie in the range 1 100-1 250°C. 

Measurements of solidus and liquidus temperatures need to be established. 

The compounds of Mg with Ca, Sr and Ba are also simply prepared mixtures of different proportions are heated to above the liquidus temperature and cooled for examination under inert conditions. Single crystals can be picked out from those alloys that contain a distinct compound phase as detected by x-rays. ... 

Intermetallic compounds are generally prepared by simply heating the elements in the correct molar proportion at or just below the liquidus temperature specified in the phase diagram. The major experimental problems associated with these methods are first, attack of the container material by the alkali metal or the intermetallic compound in the molten state second, the temperature chosen must be such as to attain true homogeneity of the intermetallic compound. 

The excess aluminum in the charge compensates for the loss of aluminum due to nonreductive air oxidation, and also provides aluminum for alloying with the niobium metal produced in the reduction. As mentioned earlier, the liquidus temperatures of niobium-aluminum alloys are lower than the melting point of niobium. The melting of this alloy and the alumina slag is achieved even with the reduced amount of heat available from the reaction implemented without preheating in the open reactor. 

The electrolysis temperature affects the electrolyte conductivity, the overpotential, and the solubility of the electrodeposit in aqueous as well as in molten salt systems. The effect of temperature is particularly important in the latter case. The lower limit of the temperature of operation is set by the liquidus temperature of the bath and the solubility of the solute. Generally, the temperature chosen is at least 50 °C above the melting temperature of... 

Negative deviation from ideal behaviour in the solid state stabilizes the solid solution. 2so1 = -10 kJ mol-1, combined with an ideal liquid or a liquid which shows positive deviation from ideality, gives rise to a maximum in the liquidus temperature for intermediate compositions see Figures 4.10(h) and (i). Finally, negative and close to equal deviations from ideality in the liquid and solid states produces a phase diagram with a shallow minimum or maximum for the liquidus temperature, as shown in Figure 4.10(g). 

Fig. 4. Comparison of activity coefficients of LiF obtained from liquidus temperatures of LiF in the LiF-KCl system with those calculated from the conformal ionic solution theory (CIS).

Flood s equation physchem A relation used to determine the liquidus temperature in a binary fused salt system. fladz i.kwa zhan flores CHEM A form of a chemical compound made by the process of sublimation. flor ez 1... 

However, certain restrictions on battery performance arise from these state-of-the-art electrolytes, for which these two indispensable components are mainly responsible (1) a low-temperature limit (—20 °C) set by EC due to the high melting point and the high liquidus temperature it confers upon the solvent mixture, and (2) a high-temperature limit (50 °C) set by LiPEe due to its reactivity with solvents. As a result, the commercialized lithium ion batteries can... 

The liquid range of a nonaqueous electrolyte system is defined at the upper limit by the temperature at which one of its components begins to vaporize (also called the bubble temperature, Ob) and at the lower limit by the temperature at which one of its components begins to crystallize (liquidus temperature, Apparently, along with restrictions im-... 

In these phase diagrams, the liquidus line represents the temperature at which one of the components crystallizes, while, below the solidus line, the whole system solidifies. Between the solidus and liquidus lines are the regions where solid and liquid coexist. Since there is no solid phase above the liquidus lines and the liquid is thermodynamically stable. Ding et al. suggested that the liquidus temperatures should be adopted as the lower boundary of the liquid phase, instead of the solidus temperatures. The patterns of these phase diagrams are... 

On the other hand, the presence of the salt, LiPEe, assists the occurrence of supercooling by increasing the solution viscosity and by depressing the liquidus temperature. At practical concentrations of LiPFe ( 1.0 M), even the solidus temperature can be circumvented, since there is no crystallization process observed for LiPFe/EC/EMC solution down to —120 °C, while the glass transition occurs at —103 °C. In such concentrated solutions, even the presence of MCMB cannot initiate crystallization, and the supercooling is completely suppressed at the cooling rate of 10 °C/min. 

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