A thermomagnetic approach was used to investigate the early stage of spinodal decomposition in the ferromagnetic Ni-29 at%Cu-21 at%Pd alloy. First, the phase relationship associated with the decomposition was determined by measuring the Curie temperature and the lattice parameter. Next it was confirmed by TEM observations that as annealed at 773 K after solution treatment, the alloy decomposes by a spinodal mechanism and result in the modulated structure. The thermomagnetic curves were measured for the alloy annealed at 773 K during various periods of time. By comparing the experimental curves with the calculated ones, assuming a sinusoidal composition fluctuation, the kinetics of the amplitude growth can be estimated in the spinodal decomposition.

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Dislocation structure formed during dezincification of Cu-4.7 at%Zn and Cu-2.8 at%Zn-0.6 at%Sn alloy was examined mainly by electron microscopy. A number of loops and dislocations were observed in the dezincified region of the Cu-4.7 at%Zn alloy. They are uniformly distributed in the diffusion zone of moderately dezincified specimens. In the latter stage of dezincification, small loops are hardly observed and subboundaries are developed. The dislocation structure is formed by annihilation of excess vacancies produced by dezincification. The dislocation density in the dezincified region of the Cu-2.8 at%Zn-0.6 at%Sn alloy was found to be much lower than that of the Cu-4.7 at%Zn alloy. Tin addition causes the suppression of vacancy loop formation and the development of dislocation structure. The results are explained by considering the trapping of dezincification-produced vacancies by tin atoms.

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Using an electric resistance sintering aparatus, 2–5%C cast iron powder compacts containing flake graphite were heated very rapidly to melt the central part of the compacts. During rapid cooling, the pores were frozen in a white cast iron matrix. The pore-containing white cast irons were annealed at 873–1223 K for 1.8 ks under dry hydrogen flow, and then cooled in air or in a furnace. Nodular graphite 5∼10 μm in diameter was distributed depending on the distribution of pores which existed before annealing. However, in the pore-free specimens remelted at 1723 K for 0.6 ks, no nodular graphite was formed. The crystal structure of the nodular graphite was polycrystalline, with the c-axis of all crystallites oriented in a radial direction, similar to that of conventional nodular graphite crystallized in a melt. These results indicate that the nodular graphite can be formed by annealing of the pore-containing white cast iron made from any kinds of cast iron powder irrespective of carbon centents. This is because carbon atoms undissolved in austenite are decomposed from cementite and precipitate as graphite on the surface of pores and then fill them up during annealing.

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The (001) surfaces of the Cu–Au alloy with various compositions have been prepared by depositing gold onto the surface of copper and by subsequent heating. The surface structures have been studied by LEED and compared with those of the bulk alloy crystals obtained by previous researchers.
By the present vaporization and heating method a series of the LEED patterns in the order of hexagonal, streak, (1×1)I, c(2×2) and (1×1), have been observed with decreasing gold content. The c(2×2) structure corresponds to the surface structure of the bulk ordered Cu₃Au crystal, while the hexagonal structure is a new structure observed on the alloy surface.

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The TTT diagram for the recrystallization of a cold-rolled Cu-10 at%Al alloy was depicted from the X-ray diffraction data. On the basis of the TTT diagram, two-step annealing procedures were adopted for investigating the effects of recovery and short-range ordering on the recrystallization-texture development.
Application of a preliminary annealing (primary annealing) at temperatures below 583 K prior to the recrystallization annealing (at 673 K for 480 s) enhanced the development of the major component of the recrystallization texture and decreased the intensity of the minor one. The primary annealing at 503 K showed the most remarkable effect on the recrystallization. A short time primary annealing at this temperature suppressed the development of the major component, whereas the prolonged one enhanced it. This may be due to the competition of the recrystallization with the short-range ordering in the recrystallization front region. A slight increase of the major texture component in the specimens primarily annealed at temperatures higher than 583 K, may have arisen from its nucleation prior to that of the other components.

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Drop Weight, Dynamic Tear and Charpy V-Notch impact tests have been carried out on ABS Grade CS steel weldments. The effects of welding parameters (process, filler metal type, heat input) on fracture resistance have been investigated. Considerable variation was observed in weldmetal impact properties as welding parameters were varied. Test results indicate that increasing the heat input per pass reduced weld metal impact properties. An empirical correlation has been derived between the weld metal Dynamic tear and Charpy V-Notch data.

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Ultra high vacuum zone refined molybdenum single crystals oriented at the center of the unit stereo-triangle (Schmid factor of (011) [1\bar11] system is about 0.5) were deformed in tension at 77 and 293 K . Thin foil specimens for transmission electron microscopy (TEM) with desired orientations were prepared from tensile specimens deformed to various strains.
TEM revealed joggy long screw dislocations, debris loops and dark spots for both deformation temperatures. Dense tangles are formed during 293 K deformation, whereas, at 77 K, no tangles are formed, but dense bands corresponding to a few secondary slip systems are formed. The densities of the above mentioned features were measured. Resistive stresses from various origins, contributing to work hardening, were estimated; the stress needed for non-conservative jog motion was found the most predominant and concluded to be the most important component of the flow stress for the low temperature type work hardening of molybdenum single crystals.

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The phase relationships in the liquid Cu–O system were determined by the following three experimental techniques, (1) Water quenching of the samples in crucible, (2) Water quenching of the samples after suction into an alumina tube, (3) Emf measurements combined with the suction-water quenching.
The cells used were as follows: Pt/Ni, NiO/ZrO₂(+CaO)/O in Cu(1) or copper oxide (1)/LaCrO₃/Pt, Pt/Ni, NiO/ZrO₂(+CaO)/O in Cu(1)+copper oxide (s or 1)/LaCrO₃/Pt.
It was confirmed that the miscibility gap exists between liquid copper and liquid copper oxide and it seems to disappear at higher temperature than 1620 K.
From emf measurements, the activities of oxygen and copper were calculated at 1573 K, and the standard free energies of formation of solid and liquid Cu₂O were determined in the temperature range from 1370 to 1600 K . Relative partial molar entropy of oxygen in the liquid Cu–O system showed a minimum value at or close to the stoichiometric Cu₂O composition.
The oxygen potential-temperature-composition (P-T-X) diagram for the Cu–O binary system was determined from the results of this study.

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The effect of solute concentration on the dehancement of solute diffusion in dilute Pb(Ag) alloy is studied.
The results suggest that there exists the split interstitial composed of two Ag solute atoms or of more complicated types of defects, and that the concentration of the split interstitial increases with increasing solute concentration and with decreasing temperature.
The binding enthalpy of a split interstitial is estimated to be larger in Pb(Ag) alloys than in Pb(Au) alloys.

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