Prediction of Heat of Fusion of Rare Earth Compounds from Binary Phase Diagrams

Based on the thermodynamical principle the new formula for calculation of heat of fusion and its error have been derived from binary phase diagrams which could be classified to eutectic,solid solution,degenerate eutectic and involving a compound phase diagram and so on.Using these formulae heats of fusion of some rare earth ox- ides have been predicted.

Estimation of Thermodynamic Properties from Binary Phase Diagram

The general relationship between binary phase diagrams and the thermodynamic properties was system- atically derived without any assumption.A procedure was presented to estimate the thermodynamic proper- ties from the binary phase diagrams.

Relationship between the types of binary alloy phase diagrams of Ⅷ and IB group elements and the Mendeleev numbers

The relationship between the types of binary alloy phase diagramsof VIII and Ib group elements and the Men- deleev numbers wasdiscussed for the first time using the VIII and IB group elements assolvent metals (A) and the other elements as solute metals (B),basesd on their alloy phase diagram types. The Mendeleev numbers ofthe solvent metals and the solute metals were expressed as M_A andM_B, respectively. A two-dimension map of M_A/M_B was drawn. It isindi- cated that there is an oblique line in the map, which dividesthe binary alloy phase diagram types of solvent metals into twosymmetry parts, the phase diagram types of the other elements withsolvent metals located at the above or down of the line respectively,while on the line, △M = 0.

ASSESSMENT AND OPTIMIZATION OF THE PHASE DIAGRAMS AND THERMODYNAMIC DATA OF SOME BINARY SYSTEMS CONTAINING PRASEODYMIUM CHLORIDES

In this paper a critical assessment and optimization of the phase diagrams and thermodynamic properties of the PrCl_3-MCl(M=Li,Na)and PrCl_3-MCl_2(M=Mg,Ca,Sr,Ba) binary systems have been per- formed.The assessed and optimized binary phase diagrams and thermodynamic data with self consistency are a better basis for constructing multicomponent phase diagrams.

ASSESSMENT OF THERMODYNAMIC DATA AND STABILITY OF INTERMETALLIC COMPOUNDS

Based on principles of thermodynamics, it is derivd that in binary system the quasi-parabola regulation must be obeyedby the standard Gibbs free energy of formation of a compound.Extending to ternary system a quasi-paraboloid regulation also must be done. The stability of some intermetallic compounds in binary systems is decided

Effect of Solute Elements and Cooling Rate on Strain in Brittle Temperature Range of Continuously Cast Strand

A micro-segregation model of solute elements in mushy zone with δ/γ transformation during solidification was established based on the regular hexagon transverse cross section of dendrite shape proposed by finite difference method under the non-equilibrium solidification condition. The model was used to calculate the non-equilibrium pseudo binary Fe-C phase diagram and the strain of steels induced by variation of temperature in brittle temperature range. On the basis of the phase diagram and the strain, the strain curve in brittle temperature range as a function of carbon content for continuously fast strand was introduced and obtained, Solute elements change the position of the strain curve. And cooling rate changes the position arid the shape of the strain curve. The comprehensive formula of the strain as functions of solute elements and cooling rate in brittle temperature range has been obtained by nonlinear fitting program.