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The thermodynamic data for solid, liquid phases in Cu-Sb and Cu-Sn binary systems were optimized from experimental thermodynamic and phase diagram data. The ternary thermodynamic parameters for liquid phase in Cu-Sb-Sn system were represented by Muggianu model and optimized from ternary isoactivity data. The calculated thermodynamic data and phase diagrams of binary systems were in good agreement with experimental data. The more correct experimental ternary data are needed. All the thermodynamic data used in calculation are presented.

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The standard Gibb`s free energy of the reaction, CO+(1/2)O₂=CO₂, was measured by using zirconia solid electrolyte with the reference electrode of Ni-NiO mixture or air. In order to reduce the influence of the partial electronic conduction parameter on measuring the standard Gibb`s free energy of the reaction, P_(co₂)/(P_(co₂)+P_(co))≥0.8 was used for the air electrode and P_(co₂)/(P_(co₂)+P_(co))≤0.6 for Ni-NiO mixture electrode. The result of the present work was as follows: CO+(1/2)O₂=CO₂, ΔG°_(co/co₂)=-276, 390-3.47TlnT+59.0T(±470) (J·㏖^(-1))(880-1270K) This was in good agreement with Chipman`s result.

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The relationship between microstructure and mechanical properties of the near-βTi-10-V2Fe-3Al alloy has been investigated. Microstructural variations were made by either changing heat treatment or imposing the thermomechanical processing prior to heat treatment. In the β-solution treated(ST) and aged structure, brittle fracture occurred during the tensile tests, presumably due to the precipitations of fine secondary a particles in the metastable β matrix. The presence of primary a in the (α+β)-ST and aged structure represented high ductility, about 10%. The increase in ductility was, however, limited by the formation of thick grain boundary α-film. Thermomechanical processing was found to be effective in increasing yield and tensile strength of the alloy. In order to get a good combination of strength and toughness it is thus, suggested that microstructure should be modified not to contain any grain boundary α, but to contain globular primary αin small β grains.

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Localized neck was assumed to be initiated by slip on the plane where pure shear condition is attained. From this concept an instability criterion was derived in terms of work harden ing exponent n and the strain ratio R. Hill`s yield criterion proposed in 1948 was employed in the derivation considering only normal anisotropy. The resulting criterion provided entire forming limit diagram in all combinations of major and minor strains with reasonable accuracy for several typical metals.

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