Molecular dynamics (MD) simulation of an amorphous Pd₈₀Si₂₀ alloy has been carried out to know the microscopic structure in this system. After adjusting parameters of the proposed pair potentials, we have obtained similar structure factor of the simulated system to the experimental one and found some trigonal prismatic structures in the simulatd system, which are not always predominant. Most probable coordination number of Pd around Si is 7, which is the same as that obtained by Distorted Prismatic Packing model proposed by Gaskell.

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The effect of Al and Ni contents on the pseudoelastic behavior of Cu–Al–Ni alloys above A_f has been investigated using rapidly quenched single crystals with nearly ⟨001⟩ orientation. The results obtained are as follows: One-stage pseudoelasticity due to consecutive β₁\ ightleftarrowsβ₁′\ ightleftarrowsα₁′ transformations on loading and unloading appears in Cu-13.9Al-5.0Ni (mass%) alloy above a critical temperature of the transformation type, from β₁→β₁′ to β₁′→α₁′, T_c,1=2^L. However, such complete one-stage pseudoelasticity does not appear in Cu–14.4Al–3.6Ni and Cu–14.5Al–3.0Ni alloys because the α₁′ martensite is stabilized by the occurrence of slip deformation inside it and some strain remains on unloading, although one-stage yielding accompanied by a prior peak is observed due to the consecutive transformations on loading. The one-stage yielding on loading is not observed in Cu–14.1Al–4.2Ni alloy, since T_c,1=2^L of the alloy reaches a temperature where some aging effect occurs. The effect of compositions on those consecutive or successive transformations has been examined in detail with respect to various parameters such as M_s for γ₁′ martensite, critical stresses for the β₁→β₁′, (σ₁^L), and β₁′→α₁′, (σ₂^L), transformations on loading, T_c,1=2^L, critical stress of transformation type, σ_c,1=2^L and extrapolated temperture of a line expressing the σ₁^L vs temperature relation to zero stress, T₁^L (σ=0)(which corresponds to a hypothetical M_s for the β₁′ martensite). Taking these effects into account, the composition for the appearance of consecutive transformations has been optimized and the origin of the high T_c,1=2^L in Cu–14.1Al–4.2Ni alloy is discussed.

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Temperature dependence of tensile strength, ductility, toughness, work-hardenability and the parameter of serrated deformation was investigated in the temperature range from 6 to 130 K for as-solutionized and peak-aged aluminum alloy A7075. The tendency for the tensile strength, elongation, toughness and work-hardening exponent to increase with decreasing temperature changes to the decreasing tendency in the temperature range from 30 to 20 K. The change in the temperature dependence of the mechanical properties corresponds to that of the amount and total number of load drop in the serrated deformation. The load drop is due to thermally assisted discontinuous glide of dislocations. Disturbance of the uniform deformation which is due to the discontinuous glide of dislocations may be the main cause for the degradation of the mechanical properties.

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The Cu–Pb–Sn ternary system has been studied by the method of equilibrium saturation with lead vapour (improved isopiestic method) at low tin and lead concentrations. The Cu–Pb solution has been chosen as a reference system. The values of interaction parameter ε_Pb^Sn have been determined to be equal to 4.93, 4.72, 4.49 at temperatures 1373, 1423 and 1473 K respectively. Results of this study are compared with the literature data. ε_Pb^X interaction parameters in Cu–Pb–X solutions have been interpreted with the concept of the relative difference of ionic volumes.

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In order to assess the protectiveness of preformed Al₂O₃ scale in an H₂-10%H₂S atmosphere and the influence of Hf addition on it, Fe-10 mass%Al alloys with or without Hf were oxidized in pure O₂ at 1300 K for specified periods up to 400 ks and subsequently sulfidized at 1200 K without an intermittent cooling. The addition of 0.088 mass%Hf suppresses the formation of wavy scales which are often associated with mechanical defects and improves the mechanical soundness of the scale. As a result of this the protection time also increases. These benefits were considered to be due to the modification of the mode of diffusion through the scale. The complete prevention of sulfidation by the scale was found to be impossible, since sulfides were formed on scales which looked very sound.

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The occurrence of white iron in the interior of otherwise gray casting and a gray surface rim in a nominally white iron casting is contrary to general expectations. These phenomena, called inverse chill and inverse grayness respectively, affect cast metal quality and have important practical consequences. Hence, the sometimes conflicting published data was examined and a number of experiments were carried out to evaluate the apparent anomalies, using vacuum-refined, highly pure synthetic and commercial (Sorel F-10, S-125) Fe–C–Si alloys. The effects of various foreign elements on the formation of inverse chill were also studied by adding them singly in a highly pure form to the vacuum-refined alloys. Measurements of the cooling rates were made at the centre and top and bottom surfaces of the solidifying ingot to verify the relationship between the differential cooling rate and inverse chill.
Argon, oxygen, hydrogen and sulphur were found to be critical to the formation of inverse chill (occurrence of carbides). This study indicated that inverse chill can result from: (a) slow growth of nodules; (b) segregation of carbide-stabilizing elements towards the centre; (c) reduction of the carbon equivalent value, mainly by a reduction in silicon content; (d) the presence of oxygen or argon in the melt.

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The range of graphite forms observed in vacuum-treated Fe–C–Si alloys was studied using synthetic and commercial alloys (Sorel F-10, S-125) in order to attain a better understanding of the thermal and chemical conditions governing the growth of the various graphite forms. High-purity Fe–C–Si alloys were further treated by 3-h vacuum-refining and allowed to solidify in situ as well as in an unheated ceramic mold under vacuum. The effects of various foreign elements such as sulphur, oxygen, argon, nitrogen and hydrogen were studied by adding them singly to the vacuum-refined high purity Fe–C–Si alloys. The results are reported.
There appeared to be some confusion in the literature, particularly regarding the vermicular/coral and the compacted forms, both in the terminology used to describe them and in their sequential order in the graphite morphology “spectrum”. Hence an attempt has been made to clarify the situation in order to develop a clearer understanding of graphite morphology control.

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We have developed a new copper-carbon fiber composite which possesses properties of copper, i.e., excellent thermal and electrical conductivities, in combination with a property of carbon fiber, i.e., a small thermal expansion coefficient. The composite properties can be controlled by the amount, type and orientation of the carbon fibers they contain. Therefore, this composite is considered to be useful as an electrical material.
The effects of volume and arrangement of fibers on the thermal conductivity, electrical conductivity and specific heat of the composite were studied. The results obtained were as follows:
(1) The thermal and electrical conductivities of the composite became smaller as the volume of carbon fibers increased, and they were also influenced by the fiber arrangement.
(2) The above conductivities could be calculated by careful application of the “rule of mixtures” for composites.
(3) The specific heat of the composite was dependent not on the fiber arrangement but on the fiber volume.
(4) In thermal fatigue tests, no degradation in electrical conductivity was observed.

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