Measurements of Young’s modulus at −150∼400°C and of rigidity modulus and hardness at room temperature have been performed for Mn–Cu–Fe alloys subjected to a varying set of heat treatment and cold working. A distinct knee which may be related to the paramagnetic \ ightleftarrows antiferromagnetic transformation can be seen in each Young’s modulus vs temperature curve for the compositions of 20.13∼55.00% copper and 2.55∼30.25% iron when slowly cooled after heating at 900°C for 1 hr. Room-temperature values of Young’s modulus in the state of annealing are higher than those in the state of cold working or water quenching, and the difference between the above states becomes prominent as the manganese or the iron content is increased. The temperature coefficient of Young’s modulus is remarkably changed by alloy composition and also by annealing, cold working, water quenching and reheating after cold working or water quenching. Large positive maxima which are observed in the temperature coefficient of Young’s modulus vs temperature curves indicate the Elinvar property of these alloys. Room-temperature values of rigidity modulus and its temperature coefficient show variations smilar to those of Young’s modulus and its temperature coefficient with methods of heat treatment, reduction rate and composition. The hardness undergoes a very complicated variation with composition, reduction rate, and methods of heat treatment, ranging in Vickers hardness from approximately 130 to 800. Both corrosion and oxidation resistivities of the ternary alloys are very high.

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Crystal structures and magnetic properties of Rh–Mn–Sb alloys have been investigated by means of X-ray and magnetic analysis. It is shown that Cl_b type alloys exsist near the stoichiometric composition in the Rh–Mn–Sb system. Rh_0.90 Mn_1.20 Sb_0.90 and Rh_1.10 Mn_1.10 Sb_0.80 alloys with the crystal structure of the Cl_b type have lattice parameters of about 6.145 and 6.170 Å at room temperature, saturation magnetizations of 79.5 and 75.0 emu/g at absolute zero, saturation magnetic moments of 3.19 and 3.29 μ_B per Mn atom at absolute zero, and Curie temperatures of 325 and 350°K, respectively. Moreover, the reciprocal magnetic susceptibility of these alloys has been found to satisfy the Curie-Weiss law above the Curie temperature.

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Measurements have been made of the Young’s modulus at −150∼400°C and the rigidity modulus and its temperature coefficient at room temperature for Mn–Cu–Mo alloys subjected to cold working and various heat treatments. The results of measurements show the appearance of an anomalous variation, which seems to be related to the antiferromagnetic \ ightleftarrows paramagnetic transformation, on the Young’s modulus vs composition curves for the ternary alloys in the state of slow cooling after heating at 900°C for 1 hr. In general the Young’s modulus at room temperature in the state of annealing is higher than that in state of cold working or water quenching, and its value shows the tendency to increase with rise of the reheating temperature after cold working or water quenching. The temperature coefficient of Young’s modulus undergoes a remarkable variation by annealing, cold working, water quenching, and reheating after cold working or water quenching. The temperature coefficient is also found to vary greatly with composition. There appear positive values of the temperature coefficient of Young’s modulus in the wide range of composition, proving the alloys to have the Elinvar characteristics. The changes in rigidity modulus and its temperature coefficient with composition, heat treatment and cold working closely resemble those in Young’s modulus and its temperature. The vickers hardness shows a complicated variation in the range of the order of 130∼700 with composition and the state of cold working, water quenching or thermal treatment after cold working and water quenching. The corrosion resistance of the ternary alloys is found to be fairly satisfactory.

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Ni–Mn alloys containing less than 25.70% manganese were melted in argon atmosphere and then heated in hydrogen atmosphere at high temperatures. The alloys thus treated were cooled from 650°C at various rates or further baked at different temperatures below the order-disorder transformation point. The highest initial permeability of 24500 was shown by a Ni-20.50% Mn alloy which was heated in hydrogen atmosphere at 1150°C for 3 hr and cooled from 650°C to room temperature at 10°C/hr, and the highest maximum permeability of 93000 by the same alloy which was further baked at 400°C for 8 hr after the same heat treatment. These values are by far greater than those for “Nimalloy” of 21.91 and 22.00% Mn which were melted in air and heated in vacuum at 900°C for 1 hr. This alloy showed the hysteresis loss of 2.73 erg/cm³/cycle and the coercive force of 0.0048 Oe for the maximum magnetic induction of 2000 G, its intrinsic magnetic induction and electrical resistivity being 1970 G and 56.5 μΩ-cm (20°C), respectively.

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The quench aging of Zr–H and Zircaloy–H alloys has been studied by the resistmetric technique. A two-stage precipitation is observed, with the formation of a metastable phase before that of stable hydride phase below about 210°K. This metastable phase in thought to be the cluster of hydrogen atoms.

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An order-disorder transition of Ag₃In was investigated by means of specific heat, electrical resistivity and magnetic susceptibility measurements, and X-ray diffraction using an Ag-25at% In alloy. Specific heat vs. temperature curve shows a λ-type anomaly with a maximum at 214°C, and the heat of transition was found to be 220 cal/g-atom. From the X-ray analysis, no difference is found in the axial ratios between the low-temperature and high-temperature phases. From the result of magnetic susceptibility, a minor change in the electronic structure was suggested.

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Recrystallization and grain growth kinetics were studied for Ti–O alloys (0.04∼0.45 at%O). The recrystallization temperature increased with increasing oxygen concentration. Grain growth obeyed the growth law
ln(d\barD⁄dt)=ln(k₀⁄3)−2.0ln(\barD)
or
\barD³−\barD₀³=k′₀exp(−Q⁄kT)t,
where \barD is the mean linear intercept grain size at time t, \barD₀, the initial grain size, k′₀ a constant and Q the activation energy for grain growth. The value of Q decreased from 52.8 to 44.8 kcal/g-atom with increase in oxygen concentration. Empolying Cahn’s impurity dragging theory, the activation energies for the migration of solute-free boundaries and of oxygen atoms in alpha titanium were calculated to be 56 and 37 kcal/g-atom, respectively.

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Recrystallization and grain growth kinetics were studied in Ti–C alloys (0.07∼0.36 at%C). The recrystallizatron temperature increased with increasing carbon content. Grain growth obeyed the growth law
ln(d\barD⁄dt)=ln(k₀⁄3)−2.0ln(\barD)
or
\barD³−\barD₀³=k′₀exp(−Q⁄kT)·t,
where \barD is the mean linear intercept grain size at time t, \barD₀ the initial grain size, k′₀ a constant and Q the activation energy for grain growth. The value of Q decreased from 52.8 to 46.7 kcal/g-atom with increase in carbon content. Employing Cahn’s impurity dragging theory, the activation energies for the migration of solute-free boundaries and of carbon atoms in alpha titanium were calculated to be 56 and 42 kcal/g-atom, respectively.

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A remarkable solution softening phenomenon was found in the tensile test of Al–Mg–Zn alloys at high temperatures. The effect of zinc addition was studied and the softening mechanism is discussed. The results are summarized as follows:
(1) The flow stress level of Al-3.3 at%Mg alloy decreased linearly with increase in zinc concentration. The decreasing rate was about 4% per 1 at% of zinc.
(2) The high temperature deformation behaviors of Al–Mg alloys was not changed essentially by the addition of zinc. For both binary and ternary alloys, the following mechanical equation of states is given:
\dotε=Aσⁿexp(−Q⁄RT),
where \dotε is the strain rate, σ the applied stress, A a constant depending on the concentration of zinc, n=3.3, Q=36∼37 kcal/mol and RT has its usual meaning.
(3) The high temperature deformation of Al–Mg–Zn alloys as well as that of Al–Mg alloy is governed by the viscous motion of dislocations which drag magnesium atmospheres formed around them. The solution softening observed can be attributed to the enhanced diffusivity of magnesium which is caused by the addition of zinc.

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The removal of impurities in mattes and white metals was studied using a sample weighing 100 g under reduced pressures at 1200°C. After the vacuum treatment at around 0.5 mmHg for 1 hr, almost all impurities (Pb, As, Sb, Bi, and Zn) in mattes were reduced below 0.1%. Arsenic in white metal was not removed under the same condition.
Chemical and X-ray diffractive analyses of sublimates revealed that appreciable fractions of impurities were in metallic states. A thermodynamic discussion supported also the evaporation of impurities as metal vapors and sulfide vapors.

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For the purpose of obtaining a fiber-strengthened metal by cold working a two-phase alloy, we chose the Cu–(Fe–Ni–Mo) system as a suitable system. The copper wires containing fibers of a strong iron-rich phase in the ductile copper-rich matrix were fabricated by cold drawing the iron-rich secondary phase of Cu–(Fe–Ni–Mo) alloys. The wires were quenched from 850°C followed by refrigeration for 1 hr at −196°C and subsequently annealed at 480°C for various periods of time. Electron micro-probe analysis revealed that the composition of these iron-rich phases was close to that of iron-nickel-molybdenum maraging steel. The volume fractions of the iron-rich phases in these alloys were nearly 10, 20 and 40 pct. The copper wire containing about 40 vol % iron-rich phase indicated the strength up to 80 kg/mm², with nearly 15% elongation.

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