The electrical resistivity (ρ) of Ni-base alloys containing Fe up to 30 at% has been measured in the temperature range from 4.2 to 1600 K. The concentration dependence of residual resistivity in Ni–Fe alloys, which received the atomic ordering, furnace-cooling and water-quenching heat-treatments, suggests the formation of the L1₂-type superlattice at Fe concentrations higher than 14 at%. The Curie temperature, which was determined as the inflection temperature in the ρ-T curves, agrees well with that determined by the previous magnetization measurements. The correlation between the magnetic resistivity and the ferromagnetic properties is discussed from the viewpoint of the scattering process of conduction electrons due to the localized-spin disorder.

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A thermodynamically stable quasicrystalline phase with an icosahedral structure was found to be formed at atomic compositions of Al₇₀Pd₂₀Mn₁₀ and Al₇₀Pd₂₀Re₁₀ in conventionally solidified and fully annealed states as well as in a rapidly solidified state. The substitution of Mn by Re leads to an increase in the intensity of the X-ray reflection peaks resulting from the fundamental lattice, while the intensity of the superlattice reflection remains unchanged. This result suggests that Re and Mn atoms occupy predominantly the fundamental lattice site and the superlattice site is occupied by Pd. These icosahedral alloys with an ordered structure remain stable up to the onset temperature of fusion and the icosahedral Al–Pd–Mn alloy has solidification morphology of an icosidodecahedron with a size of 0.3 mm. The formation and stability of these icosahedral alloys were examined in terms of electronic parameter and atomic size and the criterion of the high stability was clarified to be analogous to that for the Hume-Rothery type compounds.

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Amorphous Al–La–Cu alloys exhibiting a wide supercooled liquid region and a high reduced glass transition temperature (T_g⁄T_m) were formed over a compositional range from 25 to 85 at% La and 0 to 60%Cu by melt spinning. The temperature span ΔT_x (=T_x−T_g) between T_g and crystallization temperature (T_x) reaches as large as 59 K for Al₂₀La₅₅Cu₂₅. The T_g⁄T_m is also as high as 0.68 for Al₂₀La₅₅Cu₂₅ and the Al–La–Cu alloys are concluded to have a high glass-forming ability. The T_x and hardness (H_v) increase with increasing Al and Cu contents in the range from 430 to 575 K and 140 to 300 and the tensile strength also has a similar compositional dependence in the range of 535 to 880 MPa. The compositional effect on T_x and H_v was presumed to originate from the variation of the atomic configuration which reflects the compounds of La₃Al, La(Al, Cu) and La(Al, Cu)₂. The high stability of the supercooled liquid against the precipitation of crystalline phases in the vicinity of the stoichiometric composition Al₁La₂Cu₁, i.e., large ΔT_x and high T_g⁄T_m, seems to result from an optimum bonding state of the constituent atoms for the stoichiometric alloy.

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Bulk (40 g) melts of hypo- and hyper-eutectic alloys of Fe–Cr–C and Co–Cr–C have been undercooled by melting under a boron-free soda-lime silicate glass. Faceted primary M₇C₃ did not nucleate austenite and cobalt respectively as expected from the Sundquist and Mondolfo hypothesis. To explain this result, additional experiments were carried out on the simpler Ag–Ge system which has been investigated by both Sundquist and Mondolfo and the author.
Bulk (≥50 g) samples of hypo-and hyper-eutectic alloys of Ag–Ge were undercooled by melting under a soda-lime glass slag. Under these conditions, primary nonfaceted silver (actually silver solid solution) did not nucleate faceted germanium but primary germanium nucleated silver. The primary germanium which grew rapidly from the undercooled melt contained growth twins. It is hypothesized that the growth twins within the primary germanium produced submicrometre re-entrant crevices on the surface of the germanium and that these crevices were responsible for the nucleation of silver by the primary germanium. The results for undercooled hypo- and hyper-eutectic samples of Fe–Cr–C and Co–Cr–C can also be explained by this hypothesis. Faceted primary M₇C₃ did not nucleate austenite and cobalt respectively as expected from the Sundquist and Mondolfo hypothesis since the primary M₇C₃ grew slowly from an undercooled melt without growth twins.

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The three-stage work hardening in high purity iron single crystals was investigated between room temperature and 373 K with special attention to stages 0 and I, and mechanisms for these stages are proposed.
With increasing temperature from room temperature to about 350 K, the size of stage 0 decreases and the length of stage I increases. The hardening rate in stage I decreases with increasing temperature and becomes negative (work softening) above a temperature which depends on the crystallographic orientation of the specimen axis. The secondary screw dislocations are produced before the macroscopic yielding, and act as the forest dislocations to produce jogs on the primary screws. This process is the cause of stage 0. The work softening is caused by the annihilation of these jogs. The density of secondary screws produced before the macroscopic yielding decreases with increasing temperature and hence stage 0 becomes smaller. The length of stage I is determined by the dislocation structure formed in stage 0, so that it depends on temperature.
Above about 350 K, the mobility of screw dislocations approaches that of edge dislocations and little secondary screws are formed before the macroscopic yielding. The work hardening behavior is similar to that in FCC metals in this temperature range.

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A study of thermodynamic properties of the liquid Sb–Tl and Bi–Tl systems has been carried out by the galvanic cells of
\ominusW/Tl(1)/TlCl(NaCl, KCl)/Sb–Tl(1)/W⊕ (for N_Tl=0.10–0.90 at 953 to 1230 K)
and
\ominusW/Tl(1)/TlCl(KCl, LiCl)/Bi–Tl(1)/W⊕ (for N_Tl=0.10–0.90 at 667 to 1183 K).
The reliable values of E.M.F. are obtained for both systems.
The activities of both components in these systems indicate negative deviations from Raoult’s law over the whole concentration range. The activities of both components for the Bi–Tl system exhibit moderately greater negative deviations than those for the Sb–Tl system, suggesting the reasonably larger affinity of thallium for bismuth than that for antimony.
From the features of α functions of thallium for both systems, these alloys are not considered as regular solutions in either case.
The maximum values of the heat of mixing are −3.35 kJ/mol at about N_Tl=0.65 for the Sb–Tl system and −4.69 kJ/mol at about N_Tl=0.61 for the Bi–Tl system.
In addition, other thermodynamic functions were calculated on the basis of the results obtained.

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Phase relations in the Pt–GdPt portion of the system have been determined at 1100 K by X-ray and microscopic examination of quenched samples equilibrated for 610 ks. Five compounds have been identified; GdPt₅, ‘GdPt₃’, GdPt₂, Gd₃Pt₄ and GdPt. The phase GdPt₃ with AuCu₃ type structure has not been reported earlier. The compound GdPt₃ is nonstoichiometric with a homogeneity range extending from 23 to 28 mol% Gd. The phase GdPt₂ has a narrower nonstoichiometric range varying from 32 to 33 mol% Gd. The relative partial Gibbs’ energy of Gd in the two-phase fields has been determined in the temperature range 925–1125 K using solid state galvanic cells incorporating single crystal CaF₂ as the solid electrolyte and an equimolar mixture of Gd+GdF₃ as the reference electrode. The Gibbs’ energy formation of the intermetallic phases per mol has been derived from these measurements:
Gd_0.17Pt_0.83:ΔG^M=−60650+1.30 T(±80) J/mol
Gd_0.23Pt_0.77:ΔG^M=−78220+1.81 T(±180) J/mol
Gd_0.28Pt_0.72:ΔG^M=−91686+2.077 T(±290) J/mol
Gd_0.32Pt_0.68:ΔG^M=−94750−2.53 T(±300) J/mol
Gd_0.33Pt_0.67:ΔG^M=−96135−2.11 T(±310) J/mol
Gd_0.43Pt_0.57:ΔG^M=−103575−1.31 T(±360) J/mol
Gd_0.50Pt_0.50:ΔG^M=−104000+0.80 T(±380) J/mol

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An improved sessile drop technique was used to measure the changes in contact angle of a reaction system (Al/MgO). By plotting the results on a logarithmic time scale, the authors arrived at a new understanding of the wetting process. It was found that the contact angle progresses through three phases and that it is necessary to adopt the values of phase II in order not to overestimate wetting. The relationship between interface diameter and contact angle was investigated and the conditions characterizing wetting increase were defined.

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An amorphous Pd₄₈Ni₃₂P₂₀ alloy was formed by mechanical alloying (MA) of the pre-alloyed ingot for the periods longer than about 72 ks (20 h). The amorphous alloy prepared by MA for 1.08 Ms (300 h) translated into a supercooled liquid accompanied by a distinct glass transition (T_g) at 581 K, followed by crystallization at 621 K. In addition, the difference in specific heat between amorphous solid and supercooled liquid and the heat of crystallization (ΔH_x) are 10.5 J/mol·K and 3.90 kJ/mol, respectively. Compared with the data on an amorphous Pd₄₈Ni₃₂P₂₀ prepared by liquid quenching, the onset temperature of structural relaxation decreases accompanied by an increase of the heat of structural relaxation in the low temperature range below 450 K. Furthermore, an endothermic peak combined with an increased temperature dependence of specific heat appears near T_g while there is no distinct difference in T_g and ΔH_x. It is therefore interpreted that the MA-induced amorphous phase has a disordered structure with a more developed short-range ordering and contains a larger milling-induced stored energy as compared with the melt-spun amorphous alloy.

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Densification and microstructural development of stainless steel powder during hot powder vehicle compaction was investigated. The preheated powder preform, vacuum encapsuled in a borosilicate glass, was compacted in a steel dieusing preheated alumina granules as a pressure transmitting medium. The condition for the full densification was determined as a function of pressure and temperature. Three microstructural features were observed during the compacting process; solutioning of dendritic structure, recrystallization and normal grain growth, each of which was found to be mainly dependent on preheating temperature. It has been found that a submicron-sized microstructure is formed during the recrystallization stage. Kinetic analysis showed that plastic flow is a dominant mechanism of densification of the present compaction process.

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In order to establish the application of a superplastic alloy as a matrix of fibre reinforced metals, bonding of fibre with metal matrix was investigated on the hot pressed composites. A superplastic zinc alloy was used as a metal matrix and a SiC multifilament fibre tow was embedded as a reinforcement in the composites. A bonding characteristic was investigated using an optical microscope.
Enough spreading of the fibre tow and favorable bonding of the matrix metal required a sufficient flow of metal matrix. The effect of bonding temperature on the bonding characteristic was negligibly small in the temperature range between 473 and 523 K. The bonding characteristic became critically worse as the number of fibre tows increased and the thickness of matrix metal plate decreased. The metal mold set in a hot press restricted the matrix metal flow, resulting in a poor bonding. The bonding characteristic in the composites was favorable without using the metal mold.

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