An investigation was made of the influence of minerals having water of crystallization on X-ray fluorescence analysis of iron ores using a briquetting technique. An electron microscope, a derivatograph, an infrared spectrometer and an X-ray diffractometer were used together with a fluorescent X-ray spectrometer in this investigation. The results obtained are summarized as follows: (1) The weight of iron ore is considerably decreased by grinding for about 10 min. The weight loss gives a considerable influence on the fluorescent X-ray intensity of iron in iron ore. The analytical precision can be greatly improved by correcting the fluorescent X-ray intensity with the weight loss. (2) The minerals having water of crystallization like goethite (α-Fe₂O₃·H₂O) and kaolinite (Al₂O₃·2SiO₂·2H₂O) are dehydrated by grinding iron ores for about 10 min. (3) Against the dehydration, cobalt (Co₂O₃) is fairly effective as an internal standard for the X-ray fluorescence analysis of iron in iron ores. The internal standard material (Co₂O₃) must be added to iron ores before grinding for its better performance.

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Rosette patterns consisting of prismatic dislocation loops were introduced in a nearly perfect copper crystal by surface indentation. The individual surface half loops were revealed by X-ray topography as well as by etch pitting. The one to one correspondence between etch pits and dislocation images on topographs was confirmed and motion of half loops was discussed.

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The object of this study is to investigate precipitation behavior during aging of age-hardenable Fe–Ni–Mn martensitic alloys by means of specific heat measurement, thermal differential analysis, electron microscopic observation, and X-ray and electron diffractions. The as-quenched structure before aging is lath martensite. In the initial stage of aging, very fine zones with high solute concentration are homogeneously formed due to the two-phase decomposition. Subsequently the zone acts as a nucleus of the fct NiMn phase. As the zone changes to the fct NiMn particle the hardness of the alloys increases up to its maximum value. The main cause of the age-hardening is considered to be the strain hardening due to the coherency strain between zone or NiMn particle and matrix. In the over-aging and softening processes, NiMn particles grow into disc-like platelets on the (100) planes of the matrix, and the crystallographic orientation relationship with respect to the matrix is determined to be (011)_α′4°(111)_NiMn, [\bar1\bar11]_α′8°[\bar101]_NiMn. In the final equilibrium state, NiMn particles disappear and the structure is microduplex lamellae consisting of austenite and ferrite (or martensite) phases. The Kurdjumov-Sachs relationship holds between the austenite and ferrite.

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The diffusivities of Zn in Al and Al-5 wt% Zn-2 wt% Mg alloy were determined by the residual-activity method with radioactive tracer ⁶⁵Zn in the temperature ranges of 165∼645°C and 165∼560°C, respectively.
The temperature dependences of the diffusivities of Zn in Al and its alloy are given by the following equations:
D_Zn/Al=(0.177_−0.037^+0.047)exp{−(28.2±0.3)kcal⁄mol⁄RT}cm²⁄sec, and
D_{Zn/Al–Zn–Mg}=(0.682±0.017)exp{−(29.8±0.02)kcal⁄mol⁄RT}cm²⁄sec.
We have evaluated the difference in activation energy (ΔQ) between the impurity diffusion of Zn in Al and the self-diffusion of Al by means of the oscillating potential and Le Claire’ theory. The result shows that the theoretical value of ΔQ agrees well in both sign and order of magnitude with the experimental value.

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Thermodynamic properties of the binary melt PbO–B₂O₃ and the ternary melts PbO–B₂O₃–Li₂O(Na₂O, K₂O) have been studied by measuring the emf of the following cell:
Pb|PbO–B₂O₃ or PbO–B₂O₃–Li₂O(Na₂O, K₂O)|O₂(Pt).
The activities of lead oxide have been calculated in the temperature range from 800 to 1000°C. The partial and integral molar properties of the system PbO–B₂O₃ have been calculated at 1000°C. The results obtained are compared with previous experimental data. It was found in the ternary melts PbO–B₂O₃–Li₂O(Na₂O, K₂O) that at constant boron trioxide mole fraction, alkali metal oxide raises the activity coefficient of lead oxide in the range of compositions investigated.

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Investigations are made on how the initial scatter in wall thickness existing along the transverse section of a tube will change when the tube is hollow-sunk through a die. The samples used are tubes of phosphor deoxidized copper and those of aluminium alloys. From the experimental results it turns out that the initial standard deviation in wall thickness, when not below 0.02 mm, invariably decreases in its value. It is expected that tubes of a certain eccentricity could be improved if consecutive drawings are properly done.

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Single crystals of copper-10 at% aluminum alloy with tensile axes on the [111]–[212] line at an interval of 2° were deformed in the range between −195 and 800°C. Below 22°C the crystals with axes at 0° and 2° from [111] had lower flow stress than those with the neighbouring orientations in the later stage of deformation, due to an abrupt change of the deformation mechanism during deformation. At 200 and 400°C the work-hardening rate in the rapid hardening stage of the crystals having the axes between 4° and 8° from [111] monotonically increased with strain. From the observation of the change in the cross-sectional shape of the specimens, it was found that near the [111] axis the combination of the active slip systems varied very sensitively with the initial orientation, deformation temperature, and strain.

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Invar and Elinvar alloys have wide applications to electromagnetic and precision instrumentation engineering. Elinvar alloys are often used for delay lines.
We have studied propagation characteristics of ultrasonic waves in an antiferromagnetic Cr–Fe–Mn Invar alloy which has also the Elinvar characteristics. The results show that both the temperature coefficient of the delay time and the attenuation coefficient of ultrasonic waves in the alloy are very small showing excellent propagation characteristics and sufficient responses of output can be obtained up to the input of the order of 20 MHz.
The mean grain size of the alloy is 60.8 μ, and an intermediate scattering of ultrasonic waves between the Rayleigh scattering and the stochastic scattering occurs.
Mechanical working of the alloy such as grinding, polishing and lathing can relatively easily be done.
From the above-mentioned results, it is concluded that the antiferromagnetic Cr–Fe–Mn Invar alloy is an excellent delay medium for the propagation of ultrasonic waves.

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Concentration profiles of nickel in the (Co, Ni)O scales grown on the Co-low Ni alloys (0.45, 2.46, and 7.23 wt%Ni) over the temperature range from 1000 to 1300°C were determined by means of EPMA and then analyzed according to the analytical equation of Wagner and the differential equations of Dalvi et al.
By making use of both computation methods, the concentration profiles similar to the observed ones were obtained, but the agreement between them was found to be insufficient in the inner part of the scale. The values of P(=D_Ni⁄D_Co) and n in P_O2^1⁄n determined by the present analytical method were within the range of the literature values. These values of P and n depended on all other parameters, in particular, strongly on ξ′(NiO content at the alloy-scale interface) and k′(=k⁄D_Co⁰), respectively. In contrast with the presentation by Dalvi et al., both P and n values changed with NiO content in the oxide.
The mass balance equations at both scale interfaces were used to judge the validity of the numerically obtained solutions. The resulting solutions did not satisfy the mass balance equation at the scale-gas interface. Therefore, it was concluded that the perfect solutions could not be obtained by using the equations of Dalvi et al. This result may be ascribed to the change in the P and n values with NiO content in the oxide.
On the other hand, the equation of Wagner is suitable for an approximate estimation of the cation distribution and diffusivities in the oxide scales because of its simplified form.

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