Longitudinal and transverse magnetoresistances have been measured at 4.2 K in a magnetic field up to 1.59 MA/m over a wide concentration range through the critical concentration, where fer-romagnetism disappears, for Ni–Cu, –Pt and –Rh. Magnetoresistance anisotropy (MRA) for Ni–Pt and –Rh shows the change in sign in the concentration dependence, at which the magnetocrystalline anisotropy (MCA) also changes the sign. Forced magnetoresistance (FMR) near the critical concentration is negative in sign for Ni–Cu and is positive for Ni–Pt and –Rh. The magnitude of Ni–Cu is the largest and that of Ni–Pt is the smallest. The results of MRA and FMR are discussed in connection with the degree of magnetic homogeneity and the band character of the alloys, respectively.

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The electromotive force (EMF) of H₂|H⁺|M cell (M=transition metals and s-p metals) was measured as a function of temperature. From the measurement, the thermodynamic quantities of hydrogen-metal systems at infinite dilution limit, Δ\barG_H, Δ\barS_H, and Δ\barH_H, were obtained. These values for Ti, V, Nb and Ta (i.e. the exothermic system) were basically in agreement with the values derived from solubility data, respectively. While, in the case of the endothermic system (i.e. Mo, W, Co, Rh, Ir and Pt), the thermodynamic values measured by the EMF method, for instance, Δ\barH<0, were different from those of the solubility data. From these systematic measurements, the thermodynamic quantities obtained by the EMF method were discussed on the basis of the bonding nature of metal-hydrogen systems by considering the chemisorption of hydrogen on the metal surface.

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Measurements of electrical resistivity and elastic constants in quenched Au-47.5 at%Cd-0.75 at%Cu and Au-49.0 at%Cd-0.75 at%Cu alloys have been carried out as a function of temperature The resistivity behaviour is almost the same as that in a series of βAu–Cd binary alloys reported previously; it has been observed that the resistivity anomaly occurs at about 380 K for both alloys. In the quenched Au-47.5 at%Cd-0.75 at%Cu alloy, the elastic constants C′=(C₁₁−C₁₂)⁄2 and C₄₄ have also exhibited anomalous behaviour at about 380 K: the C′ decreases drastically and the C₄₄ increases slightly at this temperature. It has been found, on the other hand, that in the quenched Au-49.0 at%Cd-0.75 at%Cu alloy, there is no anomaly in the elastic constants C′ and C₄₄ at about 380 K in spite of the occurrence of the remarkable resistivity anomaly.
The modification of the martensitic transformation in βAu–Cd alloys by quenching is discussed on the basis of these results, and a possible explanation of the effect of quenching on the martensitic transformation is presented.

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Atom location by channelling enhanced microanalysis (ALCHEMI) under a planar channelling condition was performed to locate the ternary additions Fe, Co and Cr of about 5 at% in the intermetallic compound Ni₃Al. It is concluded that the occupation site of Fe atoms depends on the chemical composition of the compound, i.e. the averaged Ni site occupancies of Fe in Ni₇₀Al₂₅Fe₅, Ni_72.5Al_22.5Fe₅ and Ni₇₅Al₂₀Fe₅ are 70%, 42% and 23%, respectively. The Ni site occupancy of Co in Ni₇₀Al₂₅CO₅ is 94%, but that of Cr in Ni₇₅Al₂₀Cr₅ is 6%, showing that Co and Cr have strong preferences in the Ni and Al sites, respectively. These results are compared with previous results obtained by APFIM and ALCHEMI under an axial channelling condition and the predictions from the thermodynamical consideration on the phase diagram. The accuracy of ALCHEMI under a planar channelling condition is also discussed for the L1₂-type ordered structure.

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Fe_1−xCu_x alloy films sputter-deposited on water-cooled substrates under Ar gas pressures, P_Ar=8.9 and 0.23 Pa, were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction measurements. The SEM and TEM studies show that the alloy films made under P_Ar=8.9 Pa have a columnar structure with a grain size of about 20 nm, while those made under P_Ar=0.23 Pa have a fibrous structure with a grain size of about 10 nm. The primary solid solutions of both bcc and fcc phases are extended in the Fe-rich and Cu-rich regions, respectively in contrast to no solid solution in the equilibrium phase diagram. In the Fe_1−xCu_x alloys made under a high P_Ar, moreover, the single phase regions more widely extend and the oxide phase, CuFeO₂, coexists.

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The effects of microstructural factors on irradiation growth of zirconium-base alloys have been evaluated on the basis of a growth model in which point defects parameters obtained by molecular dynamics are used. Comparison of experimental data on specimens with well-defined microstructures and the calculated results of these data have confirmed predictive capability of the model. The calculated results show that irradiation growth could be reduced by the factors such as (1) an increase of the grain size, (2) a reduction of the grain aspect ratio, or (3) a decrease of the dislocation density.

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The densities of melts in the systems FeO–Fe₂O₃–CaO and FeO–Fe₂O₃–2CaO·SiO₂ have been measured under controlled oxygen partial pressures from the liquidus temperature to 1873 K by using the Archimedean method. The molar volumes of melts in the ternary system FeO–Fe₂O₃–CaO satisfy the additive rule. The molar volume of hypothetical liquid lime in iron oxide melts shows very good agreement with that estimated from CaF₂–CaO melts and from SiO₂–CaO melts. The densities of the FeO–Fe₂O₃–CaO melts, ρ (kgm⁻³) can be reproduced to within ±0.5% by the following equations:
10⁵⁄ρ=
(1⁄2.676)×(mass%CaO)+(1⁄4.624)×(mass%FeO)+(1⁄4.298)×(mass%Fe₂O₃) (at 1673 K)
(1⁄2.664)×(mass%CaO)+(1⁄4.588)×(mass%FeO)+(1⁄4.259)×(mass%Fe₂O₃) (at 1773 K)
(1⁄2.654)×(mass%CaO)+(1⁄4.548)×(mass%FeO)+(1⁄4.221)×(mass%Fe₂O₃) (at 1873 K)
For the melts in the system FeO–Fe₂O₃–2CaO·SiO₂, the molar volumes do not satisfy the simple additive rule. Increase of dicalcium silicate content and ferrite ions in the melt may contribute to polymerization of silicate ions, and it results in a positive deviation from the additive rule in volume. A liquid miscibility gap was observed in the system FeO–Fe₂O₃–2CaO·SiO₂.

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The densities of melts in the system FeO–FeO₂O₃–BaO and BaO–BaCO₃ have been measured under controlled atmospheres from the liquidus temperature to 1873 K by using the Archimedean method. The molar volumes of melts in the binary system BaO–BaCO₃ satisfy the additive rule. On the other hand, the molar volumes of melts in the ternary system FeO–Fe₂O₃–BaO show a possitive deviation from the additive rule and can be reproduced to within ±0.6% by the following equations:
V_M(cm³⁄mol)=15.54N_FeO+37.16N_Fe2O3+31.27N_Bao+3.05N_Fe2O3N_Bao⁄(N_Fe2O3+N_Bao) at 1673 K,
=15.66N_FeO+37.50N_Fe2O3+31.40N_BaO+2.98N_Fe2O3N_BaO⁄(N_Fe2O3+N_BaO) at 1773 K,
=15.80N_FeO+37.84N_Fe2O3+31.53N_BaO+2.91N_Fe2O3N_BaO⁄(N_Fe2O3+N_BaO) at 1873 K,
A similar positive deviation is not observed for the melts in the system FeO–Fe₂O₃–CaO. This suggests that the addition of Ba²⁺ cation results in the polymerization of ferrite anions as FeO₄⁵⁻.

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Corrosion- and wear-resistant alloys for the cylinders of fluoroplastic shaping machines were developed by the HIP (Hot Isostatic Pressing) process. To determine the optimum alloy composition, corrosion resistance of Ar arc melted alloys of various compositions was initially investigated. After the optimum alloy composition was found, the new corrosion- and wear-resistant alloys were produced by the HIP process.
The arc melted alloy to which only B and Si were added to improve the wear resistance of Hastelloy C, was rapidly corroded in hydrofluoric acid. On the other hand, the alloy with not only B and Si but also Cu added, showed the same high corrosion resistance as Hastelloy C. It was found that the addition of Cu significantly affected the corrosion resistance of Ni–Cr–Mo–B–Si alloys. The compositions of the new alloys for the cylinders of fluoroplastic shaping machines was determined. The compositions of the new alloys were Ni-15.0 mass% Cr–15.0Mo–2.5B–3.0Si–1.0Cu (named C-700) and Ni–17.5Cr–24.0Mo–3.6B2.9Si–1.0Cu (C-703). The prealloyed C-700 alloy powder was sintered by the HIP process. In the case of the C-703 alloy, the Ni–Mo–Si–Cu alloy powder and the CrB powder were reaction sintered by the HIP method. The CrB particles were transformed into M₃B₂ particles during the HIP process. The corrosion resistance of C-700 and C-703 to HF were slightly superior to that of Hastelloy C. The wear resistance of C-700 was 70 times better than that of Hastelloy C. Furthermore, the wear resistance of C-703 was 150 times better than that of Hastelloy C. It was found that C-700 and C-703 alloys have high performance for the cylinders of fluoroplastic shaping machines.

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