In a dynamic test (∼1 m/s) fine grained iron and steel show only slight elongation while coarse grained specimens show large elongation. In the fine grained specimens, showing this apparent brittleness, the deformation is concentrated near the grips and is not propagated along the entire gage length. By using the wave propagation analysis, the quasi-critical impact velocity, adequate for materials with Lüders elongation and high yield stress, has been derived. It has been shown that the smaller the grain size, the lower the quasi-critical impact velocity, in accordance with the experimental observations. The existence of the apparent brittleness, pseudo-brittle fracture, has been found in aluminum. It agrees with the prediction based on the wave propagation analysis and the work hardening characteristics brought about by the combination of high strain rate deformation and subsequent slow deformation.

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Measurements of the internal friction Q⁻¹ at a maximum shear strain amplitude of 2∼12×10⁻⁵ and a tensile stress of 1.18 MPa and of the magnetic and mechanical properties have been carried out for Fe–W alloys containing 0∼20%W . The highest Q⁻¹ value of 34×10⁻³ is obtained with an Fe-14%W alloy rapid-cooled after heating at 1200°C for 1 h. The Q⁻¹ value increases with measuring temperature T, showing a minimum near T⁄T_c=0.7 (T_c: magnetic transformation temperature). Moreover, the Q⁻¹ value shows a two-step decremental change with increasing magnetic field. The variations in Q⁻¹ and coercive force H_c with composition and/or heat-treatment are opposite to each other, i.e. the alloys having larger Q⁻¹ exhibit smaller H_c. The mechanical strength of the binary alloys increases considerably with W content.

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To study the interdiffusion between solid iron and liquid zinc, high purity iron test pieces were immersed into a high-purity zinc bath of 713–873 K . The thickness and the growth rate of alloy layers on the iron surface, and the quantity of iron reacted with zinc were measured.
A Γ phase was formed next to the iron, followed by a δ_1K phase. Up to 763 K, a δ_1P phase and a ζ phase were formed next to the δ_1K phase. The ζ phase thinned with immersion time, and disappeared at 763 K. The growth rate of the δ₁ phase was higher than that of the ζ phase. Over the temperature range between 773 and 833 K, a (δ₁+η) mixture phase was formed next to the δ₁ phase and dropped off into the bath. Above 833 K, the δ_1K phase formed on the surface of the alloy layers dropped off into the bath. Its thickness remained at about 10 μm. The total thickness of the alloy layers had a peak at about 793 K.
Up to 1200 s, the iron weight loss had a peak at 793 K, but for 3000 and 6000 s immersions it had a peak at 773 K . Above 813 K, it was greater than those of other investigations. The quantity of iron remained in the alloy layers had a peak at about 793 K, corresponding to the fact that the total thickness of the alloy layers had a peak at the same temperature; its peak value remained constant for a immersion time longer than 1200 s. The quantity of iron dissolved into the zinc bath had a peak at 773 K for a immersion time longer than 3000 s.

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The isothermal oxidation behavior of Fe–20Cr alloys with various amounts of lanthanum and with constant amounts of various reactive elements (Y, Gd, La, Al, Zr, Ti and Si) was studied in air at 1273 K.
The oxidation behavior of the alloys with various amounts of La suggested that the improving mechanism of oxidation resistance was different from those proposed previously. Seven alloying elements of 0.7% resulted in a remarkable improvement of oxidation resistance. The extent of beneficial effect of each element considerably depended on its affinity for oxygen, but the effect of La and Si additions deviated from this tendency. Internal oxidation layers were observed beneath the scale in all the oxidized alloys except for the La-containing alloys, which showed the least improving effect.
As the result, it was found that these elements had two main beneficial effects on the improvement of oxidation resistance. The first was the stabilization of the Cr₂O₂ scale with dissolving the alloying element which was followed by a drop in dissociation oxygen pressure of the scale and the second was the formation of an internal oxidation layer which was enriched under the lowered dissociation oxygen pressure induced by the first effect.
It was assumed from the thermochemical considerations that the alloying elements having strong affinity for oxygen and also high mobility in the base alloy would be more effective in the improvement of oxidation resistance.

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A graphite addition procedure proposed by the authors has been successfully applied to the determination down to the ppm range of nitrogen in powdered niobium. The optimum experimental conditions were established as follows: a 1:1 atomic ratio mixture of powdered niobium to powdered graphite was made into a pellet in cold press; the pellet was extracted in a graphite crucible at 2200–2250°C by the vacuum extraction method; and the time required for the complete extraction of a pellet weighing 0.5–1.2 g was within 30–60 min at the given temperatures. The results obtained by this method agreed well with those obtained by the Kjeldahl method. The precision of the variation coefficient was less than 5% for −60 to −325 mesh niobiums containing 0.01–0.04 wt% of nitrogen.
Results of the studies of the effect of graphite and kinetics of the release of nitrogen by the present graphite addition procedure showed that the extraction of niobium pellets with graphite at high temperature promoted the formation of highly extractive NbC, and that the rate of release of nitrogen proceeded according to the first-order rate equation, making complete extraction possible in a relatively short time at high temperature. It was found that the extraction of nitrogen was closely related to the composition of the extracted products. It was supposed that the extraction from a niobium rod in a graphite crucible was difficult owing to Nb₂C phase formation even at high temperatures.
Incorporating the use of a molybdenum crucible free from the formation of carbides allowed the nitrogen extraction at high temperature from a niobium rod, with an extended collection time for nitrogen.

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The present work deals with the applicability of statistical thermodynamic approach based on free-volume theory to copper bearing substitutional solutions. Analysis of experimental data on these systems show good agreement with the calculated values of these parameters based on the different expressions developed in this new approach.

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Amorphous alloys of a new type with excellent thermal stability and hardness have been found in extensive composition ranges in the alloy systems of cobalt-VIb group transition metals-carbon such as Co–Cr–C, Co–Mo–C, Co–W–C, Co–Cr–Mo-C, Co–Cr–W–C, Co–Mo–W–C and Co–Cr–Mo–W–C by a rapid quenching technique. Vickers hardness of these alloys increases with increase of chromium, molybdenum and tungsten and its maximum attains the value as high as about 1450 DPN. Also, the amorphous structure of these alloys is thermally more stable as compared with the other cobalt-based amorphous alloys reported so far. The highest crystallization temperature is 1042 K. The effectiveness of alloying elements on the increase in hardness and crystallization temperature becomes large in the order of chromium, molybdenum and tungsten. Such effects seem to take place by a stronger bonding force between alloying elements and carbon as compared with that between cobalt and carbon. These alloys are attractive materials because of their high hardness values with good ductility and high thermal stability.

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The shape and crystallographic orientation of crystallites in Fe films prepared at evaporation rates, 50 nm/min, 250 nm/min and 1 μm/min, have been examined. The incidence angle and the substrate temperature are 45 and 200°C, respectively. The shape is observed by replica electron microscopy for the surface and the cross-section of the film. The crystallographic orientation is analysed by means of pole figures obtained by the Schulz method. The results obtained are summarized as follows. (i) Regardless of different evaporation rates, the columnar structure was clearly observed and the inclination angle of the column axis was about 30° off from the film normal to the vapor beam direction. (ii) The top shape of columns appearing on the film surface depends on the evaporation rate and four kinds of shapes were discriminated. The film takes a texture, which depends also on the evaporation rate. (iii) The correspondence between the top shape and the texture indicates that the top of a columnar grain is surrounded by {110} planes.

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