Atomic processes associated with the solid-liquid phase transition in close packed metals are discussed.There exists a definite temperature T^* at which the resonance in vibration takes place between atoms adjacent to vacancies and atoms apart from them. A number of Frenkal defects originates in a crystalline domain around a vacancy through the chain-reaction like spreading of the resonance at T^*, and the domain results in the random arrangement. It becomes more probable to generate vacancies in the surface of crystal at T^*. The surface layer and the crystalline domain near the surface change into the disorderly arrangement of atoms due to some of surface vacancies, and others diffuse into the disordered domains and the remaining crystalline domains. Vacancies can travel easily in the disordered domain, and this means that there exist atoms in the translational motion, their concentration being identical with vacancies. Liquid is the state in which the vibrational motion coexists with the translational one. The temperature T^* is the melting point of metals which is given by (9⁄8)(kT_m⁄L₀)=0.0344. The latent heat of fusion and the entropy change on melting are evaluated in good agreement with the observation according to the above atomic processes.

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The dynamic behavior of the solid-liquid interface and crystal defect during the melt growth of a Bi thin foil (99.9% purity) has been observed using a transmission electron microscopy and a TV–VTR imaging system. The (11\bar1) film was partially melted and regrown by cooling at a rate of 8.3×10⁻³ to 2.7×10⁻¹ K/s. The growing interface was concave toward the melt when the cooling rate was low and it became nearly straight when the cooling rate was high. Moreover, three types of the interface movement were observed during the melt growth; (a) a back-and-forth oscillation at the slow cooling rate, (b) a step-wise oscillation at the intermediate cooling rate and (c) a steady advancement at the high cooling rate. The oscillatory interface motion was found to be caused by a small fluctuation of temperatures during cooling. No facet growth was seen at any cooling rate against expectation.
In the melt-grown crystals various kinds of defects were observed; (1) short and long dislocations and dislocation loops, (2) lineage defects probably composed of a dislocation array, (3) circular voids and (4) triangular defects unidentified. The formation and behavior of these defects during the melt growth and subsequent cooling processes were explained and their density and size were estimated. Among the defects introduced in crystals the following three were most dominant; short dislocations 0.1 μm in average length, dislocation loops 0.05 μm in average diameter and circular voids 0.03 μm in average diameter.

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The interdiffusion experiment and thermodynamic study of Cu-rich α Cu–Ni–Sn solid solutions have been performed in a temperature range from 1023 to 1123 K. The concentration profiles indicate that the diffusion rate of Sn is greater than that of Ni in these solid solutions. The influence of the indirect flux becomes larger with increasing Ni concentration. The interdiffusion fluxes evaluated from the equations of Dayananda and Kim show that the zero-flux planes exist in the diffusion zone of Cu–Ni–Sn couples. The diffusion paths show S-shaped curves. The direct coefficients \ ildeD_SnSn^Cu and \ ildeD_NiNi^Cu are positive, and the indirect coefficients \ ildeD_SnNi^Cu and \ ildeD_NiSn^Cu are negative. The four interdiffusion coefficients are very sensitive to the Ni and Sn concentrations. The temperature dependence of \ ildeD_SnSn^Cu, \ ildeD_SnNi^Cu, \ ildeD_NiNi^Cu and \ ildeD_NiSn^Cu at the composition of Cu-6.0 at%Ni-3.7 at%Sn can be expressed by the following equations:
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and
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The estimated values of interaction parameters indicate that the interaction energy of the Ni–Sn bond is much larger than those of the Cu–Sn and Cu–Ni bonds.

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Effects of the biaxial tensile state of stress on the crack growth behaviour, and the local deformation and cavitation near the crack tip were studied during straining of type 316 stainless steel by tension at 923 K and a strain rate of 4×10⁻⁶ s⁻¹. The crack growth rate reached a constant value after an initial acceleration for a given loading condition, and the steady state crack growth rate increased noticeably with increasing degree of biaxial state of stress. Under a higher degree of stress biaxiality, a more developed work-hardened state due to a higher strain rate, and more frequent cavitation were found to occur in a crack tip region (several 100 μm in size) where the stress (and strain) was concentrated. Further, the size of this crack tip region itself tended to become smaller. The increase in the steady state crack growth rate with increasing stress biaxiality was able to be explained phenomenologically from these findings on the local deformation and cavitation ahead of the crack.

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The corrosion behaviour of nine Zn–Al alloys, pure zinc and pure aluminium was examined in a 2 mass%HCl solution. Furthermore, the behaviour of Zn-50 mass%Al and Zn-60 mass%Al alloys cooled to room temperature by eight methods was also examined in 2 mass%HCl and 3 mass%NaCl solutions. To obtain the information on the effect of cooling conditions after coating on the corrosion behaviour of hot dip Zn–Al alloy coated steel sheet, the results obtained were discussed from the standing point of matrix structure.
Up to 60 mass%Al, a sample surface is corroded extensively, while at and above 70 mass%Al, a part of original sample surface remains uncorroded. At 10 mass%Al, a dendrite is corroded preferentially, on the contrary, an interdendritic portion is corroded at and above 30 mass%Al. The mass loss of Zn–Al alloy by corrosion decreases generally with increasing Al content of alloy, except Zn-50 mass%Al, Zn-60 mass%Al and Zn-90 mass%Al alloys. The mass loss of Zn-60 mass%Al alloy is greater than that of pure zinc.
Independent of the cooling condition and the alloy type, the mass of sample decreases in a HCl solution, while it increases in a NaCl solution. The mass loss of Zn-50 mass%Al alloy in a HCl solution decreases with decreasing cooling rate, while the mass gain in a NaCl solution increases. The mass loss of Zn-60 mass%Al alloy in a HCl solution is greater when the alloy is cooled to room temperature in 54 ks, and is smallest when the alloy is held in an alpha region and then water-quenched. In each solution, a Zn-rich portion is corroded prior to an Al-rich one.

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Oxygen partial pressure of the Cu₂O–CaO melts in equilibrium with liquid copper under a magnesia saturated condition was measured at 1573 K by means of a solid electrolyte galvanic cell technique. The chemical composition of quenched oxide samples taken at 1573 K was determined by chemical analysis for copper, oxygen combined with copper, magnesium and calcium.
The CaO content in CaO saturated cuprous oxide was 11.55 mass%. Solubilities of MgO in the Cu₂O–CaO melts were less than 0.62 mass%. The activities of Cu₂O and CaO in the oxide melts were calculated using the obtained oxygen partial pressures.

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The determination of micro-amounts of oxygen in high-purity zinc, bismuth, lead, antimony and copper by the vacuum fusion method was performed.
For the determination of oxygen in zinc, bismuth, lead, antimony, a carbon chip-tin nickel foil bath was used. After the sample was dropped into a crucible at a temperature between 973 and 1323 K, the crucible temperature was raised to 1173–1323 K at the rate of 373 K/60 s and gases were extracted for 300 s. For the determination of oxygen in copper, the carbon chip method was applied at 1723 K. The recovery of oxygen in these metal oxides by this method was 95–100%.

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The heat contents of the Sb–S and Sb₂S₃–FeS systems were measured by a drop-calorimeter in the concentration ranges of N_s=0 to 0.6 and N_FeS=0 to 1, and in the temperature ranges of 750 to 1350 K and 750 to 1500 K, respectively.
The method of quantitative thermodynamic analysis was applied to calculation of the thermodynamic quantities such as the activity of the components and the heat and entropy of mixing in the liquid Sb–S and Sb₂S₃–FeS systems. A considerably large positive deviation from a Raoultian behaviour was observed in a_Sb of the Sb–S system at 1300 K, while the sulfur pressure increased drastically at about N_s=0.6 where the compound Sb₂S₃ is located. Large positive deviations from Raoultian behaviours were also observed in a_Sb2S3 and a_FeS of the Sb₂S₃–FeS system at 1473 K in the concentration range of FeS above N_FeS=0.7.

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