Solidus temperature

For the purpose of discussion. Table 2 summarizes HSRS data obtained from a number of Al alloys and composites. It was first noted by Nieh et al [5] that the optimum temperature for high strain rate superplasticity in an alloy is either above or close to the solidus temperature. This led them to suggest that the presence of a liquid phase might have contributed to the observed HSRS. 

Fig. 5 Elongation-to-failure as a function of testing temperature for MA materials. /The left and right arrows on each curve indicate the incipient melting point and solidus temperature, respectively.

Because the appearance of a superlattice is usually well characterized qualitatively in terms of an interaction parameter w which has nothing to do, in the usual treatments, with the melting of the parent solid solution, one does not expect to find a simple relationship between the critical temperature for disordering of the superlattice, and Ts, the solidus temperature of the corresponding solid... 

Figure 1. Solidus as a function of pressure and temperature for diy peridotite, wet peridotite, pyroxenite and eclogite. This diagram illustrates the range in solidus temperatures potentially found in the intraplate tectonic setting where compositional differences and differences in volatile contents are expected compared with the mid-ocean ridge (dry peridotite).

Solidus Temperature, 13 487 Solid walls, flows near, 11 751-753 Solid waste(s)... 

ThTs Liquidus and solidus temperatures of alloy, respectively... 

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. 

Multi-Component Slags 10.6.6.3 Estimation of Liquidus and Solidus Temperatures of 382... 

More advanced techniques are now available and section 4.2.1.2 described differential scanning calorimetry (DSC) and differential thermal analysis (DTA). DTA, in particular, is widely used for determination of liquidus and solidus points and an excellent case of its application is in the In-Pb system studied by Evans and Prince (1978) who used a DTA technique after Smith (1940). In this method the rate of heat transfer between specimen and furnace is maintained at a constant value and cooling curves determined during solidification. During the solidification process itself cooling rates of the order of 1.25°C min" were used. This particular paper is of great interest in that it shows a very precise determination of the liquidus, but clearly demonstrates the problems associated widi determining solidus temperatures. 

Figure 4.5 shows the liquidus and solidus for In-Pb determined during cooling from the liquid the solidus, in this case, is a non-equilibrium boundary. This was demonstrated by Evans and Prince (1978) when they atmealed as solidified alloys for several hours just below their measured solidus. On re-heating melting occurred at a higher temperature than had been measured by DTA. The samples were then annealed for several hours just below the new measured melting temperature before being heated until melting was just observed again. The cycle was repeated until the solidus temperature became reproducible and the temperature then plotted as the true solidus. This is compared with the apparent solidus on the initial cooling experiment in Fig. 4.5. This paper shows the problems that can occur with...

An interesting and important corollary of CALPHAD calculations is to predict sensitivity factors for various important material properties, such as liquidus and solidus temperature, solid state transus temperatures, heat-treatment windows, etc. These can then be utilised both in alloy design and in production of alloys or components. 

Estimadon of liquidus and solidus temperatures of oxide inclusions in steels. The deformation of inclusions in steels has significant consequences on the hot workability of steels as well as for the mechanical properties of the final product. In order to increase their deformability there are at least three strategies (Matsumiya et al. 1987) (1), Reduction of their melting point (2), deceleration of crystallisation and (3), reducing their flow stress. If the melting point can be reduced sufficiently so that some liquid is present at the hot-working temperature, the inclusions would be expected to deform easily. 

Figures 10.9S(a,b) show isopleths calculated between (a) corium and siliceous concrete and (b) corium and limestone concrete. Comparison between experimental (Roche et al. 1993) and calculated values for the solidus are in reasonable agreement, but two of the calculated liquidus values are substantially different. However, as the solidus temperature is more critical in the process, the calculations can clearly provide quite good-quality data for use in subsequent process simulations. Solidus values are critical factors in controlling the extent of crust formation between the melt-concrete and melt-atmosphere interface, which can lead to thermal insulation and so produce higher melt temperatures. Also the solidus, and proportions of liquid and solid as a function of temperature, are important input parameters into other software codes which model thermal hydraulic progression and viscosity of the melt (Cole et al. 1984).

Alloys suitable for castings that are to be bonded to porcelain must have expansion coefficients matching those of porcelain as well as solidus temperatures above that at which the ceramic is fired. These are composed of gold and palladium and small quantities of other constituents silver, calcium, iron, indium, tin, iridium, rhenium, and rhodium. The readily oxidizable components increase the bond strength with the porcelain by chemical interaction of the oxidized species with the oxide system of the enamel (see Dental materials). ... 

The length of dendrites, L, can be estimated from knowledge of the thermal gradient and the phase diagram. For a given alloy, the temperature at the tips of the dendrites is the liquidus temperature of the alloy, Tl, and the temperature at the base of the dendrites is the solidus temperature, 7y. While this may be lower than the equilibrium solidus of the alloy, the separation of the liquidus and solidus temperatures gives an approximate indication of the relative tendency to form long or short dendrites ... 

The end of solidification, as defined here, is denoted the solidus temperature and is strongly dependent on the cooling rate. It was particularly difficult to determine the solidus temperature by thermal analysis in steels with a high carbon content. This is a result of their wide solidification ranges and very low growth rates near the end of solidification. Furthermore, eutectic reactions occurred at the end of solidification over a large temperature range which led to poorly defined minima in the derivative. 

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