Since metallurgy is not isolated from the other arts and sciences, it is important for progress at least to clarify which role it plays in the whole system.

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The thermodynamic properties of liquid Pb–Ag alloys have been measured by means of the following galvanic cells:
cell(I°) Pt/Ni–NiO/ZrO₂(CaO)/Pb–PbO/Ir–Pt
cell(I) Pt/Ni–NiO/ZrO₂(CaO)/(Pb–Ag)alloy–PbO/Ir–Pt
cell(II) Pt/air/ZrO₂(CaO)/Ni–NiO/Pt.
The activities of Pb were obtained with an accuracy of ±2%. The free enrgies, enthalpies and entropies of mixing were also obtained as functions of alloy composition. Furthermore, the standard free energies of formation of NiO(s), PbO(s) and PbO(l), and the free energy of fusion of PbO were measured.

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Ni–Fe–Nb alloys of varying thickness were annealed in purified H₂ gas at temperatures ranging from 750 to 1150°C for 1 h. The effect of sheet thickness and heat treatment on the magnetic properties of the alloys were investigated. Increasing the annealing temperature resulted in the increases of initial permeability μ_o and maximum permeability μ_m and the decrease of coercive force H_c. The alloys in the form of thin sheets with thicknesses of less than 0.05 mm showed small values of μ_o and μ_m and a large value of H_c. The effective permeability μ_e showed a peak when plotted as a function of magnetic field H. With increasing frequency, the peak values became lower and finally disappeared. The thinner the sheet, the higher the critical frequency at which the peak height disappeared. With increasing frequency, μ_e at H=5 mOe first decreased gradually and then sharply. The frequency range where the gradual decrease in μ_e occurred became much wider as the sheet became thinner and the annealing temperature was lowered. In the frequency range where the sharp decrease took place, however, the decrement in μ_e became smaller.

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Measurements of thermal expansion, Young’s modulus, magnetic susceptibility and electrical resistivity at −150∼500°C, and hardness and density at room temperature have been made for annealed Mn–Pt alloys. It has been found that Mn-10.05∼40.21% Pt alloys cooled slowly after heating at 1100°C for 4 h have distinct anomalies in the vicinity of the antiferromagnetic Néel point in the Young’s modulus vs temperature curves. The curve of composition vs temperature coefficient of Young’s modulus at room temperature exhibit a large positive maximum at the concentration of 30.10% Pt, showing the existence of the Elinvar characteristics in the Mn–Pt alloy system.

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An equilibrium diagram of Mn-19.0∼31.2 at% Ga binary alloys has been investigated by means of X-ray diffraction, thermal expansion and magnetic measurements. At room temperature the alloys show a β_Mn single phase at about 20.5 at% Ga or less, a β+ε mixed phase at 20.5∼25.0 at% Ga, and an ε single phase at 25.0∼29.3 at% Ga. With a further increase in Ga concentration, the ζ₁ phase exhibits a mixture phase of ε+ζ₁. It has been found that the intermetallic compound Mn₃Ga does not exist in the equilibrium state.

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Electromigration of carbon in a fcc Fe-0.52 wt%C alloy has been investigated by the steady state method. The drift velocity v and the effective charge number Z^* of carbon have been determined as functions of the electric current density j in the range from 38 to 1048 A/cm², at 920, 938, 960 and 980°C. A considerable deviation from a linear relationship between v and j has been found in the lower range of j, from 140 to 500 A/cm². This corresponds to the decrease of Z^* with increasing j. The electrical resistivity increment Δρ_d of γ-iron due to the solution of carbon has been investigated as a function of j and has been found to decrease with increasing j from 20 to about 500 A/cm² and to be constant over 500 A/cm². Z^* determined by the resistivity data depends on j in a similar way to that determined by the electromigration. Based on the values of Z^* and the resistivity, the true charge number of carbon is estimated to be about +1.5. It is indicated that both the electrostatic and the drag force act on carbon during the electromigration. The dependence of v on j is explained taking into account the migration of a carbon-vacancy complex.

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