The stresses of ordinary {211} plane and low angle {200} plane of electrodeposited chromium were measured by X-ray. The deposit had been obtained under current densities of 30 and 40Amp/dm² and at 30-70°C from Sargent Bath containing 250g/l of CrO₃ and 2.5g/l of H₂SO₄.
The following conclusions were drawn from the experiments;
(1) The stress measurement of the low angle {200} plane was the most desirable method for the preferred orientation of such an electrodeposited chromium.
(2) On the surface of electrodeposited chromium, there existed compressive stress, which was related with high preferred orientation. The compressive stress was gradually changed to the tensile stress with the approach to the copper base.
(3) The closest relation was found between bath temperature and stress. The highest compressive stress was observed at 40 and 50°C.

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Studies were made on the effects of rectified wave form on preferred orientation and internal stress of the chromium electrodeposited from Sargent Bath under current density of 30Amp/dm² and at 50°C.
The results obtained were summarized as follows:
(1) The high preferred orientation of ‹111› was obtained from smoothed D. C. and a deposit of random orientation was obtained from imperfect D. C.
(2) The grain diameter of the deposit from smoothed D. C. was 317Å and that from imperfect D. C. was 2718Å.
(3) Cracks were produced on the surface of deposit from imperfect D. C.
(4) Tensile stress was found on the surface of deposit from imperfect D. C.; whereas, compressive stress was found on that from smoothed D. C.

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The structure and the coloring of unsealed films of aluminum oxide, which had been anodized in various acid baths, were investigated by means of electron diffraction, electron probe X-ray microanalysis, single crystal X-ray diffraction, gas chromatogrphy, and infrared absorption spectrum analysis.
The following results were obtained:
(1) The structures of aluminum oxide films, which had been anodized in sulfuric, oxalic, and sulfo-salicylic acid baths, were identified as an amorphous alumina mixed with a small part of more crystalline or less crystalline γ-Al₂O₃.
(2) AlKα in sulfosalicylic acid film showed a chemical shift due to heat produced by electron irradiation during the observation with electron probe X-ray microanalyzer and electron microscope.
(3) Carbon in oxalic acid film formed to CO₂ at about 900°C, at which the color of film disappeared.
On the other hand, the colors of sulfosalicylic acid film and of p-phenolsulfonic acid film faded at about 700°C.
The difference in these temperatures for decolorization would be due to the effects of sulfur in the films.
(4) Carbon, included in oxalic acid film or in the film obtained from Ematal solution, would probably be present at ionized carboxyl group (COO^-).
Sulfur, included in sulfuric, sulfamic, sulfosalicylic, and p-phenolsulfonic acid films, would probably be present as sulfate ion (SO₄^2-).
(5) An oxide film, which had been anodized in aqueous solution of H₂SO₄-(COOH)₂ mixed acid, was divided into two layers according to the distribution of sulfur content; and single crystals of γ-Al₂O₃ were found in the outer layer of the film.

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The effect of rotating speed of specimen on the formation of duplex film consisting of metallic Cr and hydrated Cr oxide, and the incorporation of sulfate radical into the film was mainly investigated by galvanostatic electrolysis for a few seconds in dilute chromic acid electrolyte containing a small amount of sulfuric acid.
The results obtained were as follows:
(1) The increase in the rotating speed of specimen resulted in the increase in hydrated Cr oxide and slulfate radical incorporated into the oxide film, and the decrease in the molar ratio (oxide Cr/SO₄^2-).
The current in the 3rd branch of the polarization curve also increased with the rotating speed of specimen.
These phenomena were also observed in the increase of sulfuric acid added to the electrolyte. Therefore, it was considered that in the formation of the duplex film, the action of the increase in the rotating speed was similar to that of the increase in sulfuric acid added to the electrolyte.
(2) On addition of sulfuric acid to the electrolyte, both the amount of hydrated Cr oxide and the current efficiency for the deposition of metallic Cr increased; and each of them remarkably decreased at an apporoximately equal amount of sulfuric acid addition.
(3) An approximately linear relation was found between the amount of metallic Cr (m) and the electrolysis time (t) as showh by the equation: m=Kt-C, in which K=rate constant for metallic Cr deposition and C/K=time lag for obtaining constant current efficiency for metallic Cr deposition
(4) The metallic Cr deposition was closely related to the amount of hydrated Cr oxide and the molar ratio (oxide Cr/SO₄^2-), because the maximum current efficiency for metallic Cr deposition was obtained at the formation of thicker hydrated Cr oxide and the molar ratio (oxide Cr/SO₄^-2) of about 3.

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The effects of organic addition agents on the internal stress of nickel electrobeposited from Watts Bath was studied by using a contractometer of copper thin plate and by X-ray diffraction analysis.
The results obtained were as follows:
(1) Formalin increased the tensile stress of the nickel. Phenol and sulfuryl amide had no effects on the stress. Benzene-sulfonic acid, ana-naphthalene-sulfonic acid, p-toluene-sulfonic acid, and sac- charin Na salt decreased the tensile stress of the deposit and changed it to the compressive stress. The addition agents giving the compressive stress were found to be the compounds having the bonds of sulfo-and phenol-groups.
(2) Regardless of the kind of addition agents, they restrained the preferred orientation of (200) and (400) of the deposit, but promoted that of (111) and (331). Moreover, they decreased the effective particle diameter of the deposit and increased its micro-stress.

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The authors studied the effects of treating conditions on the surface concentration of aluminum of 18 Cr/10 Ni/Ti stainless steel aluminized by powder pack process with HCl gas.
The results of experiments were as follows:
(1) In the specimens diffusion coated with aluminum, the surface positions shifted in proportion to the amount of diffusion coating.
(2) Based on Fick's Law, apporoximate solutions of aluminum concentration curves on the formation of aluminum diffusion coated layers were calculated by considering the boundary condition that the position of specimen surface shifted with the lapse of time.
The results obtained were as follows:
(2-1) Possible explanations were offered for the change in surface aluminum concentration of the diffusion coated specimens by the results of above calculation.
(2-2) The main factors controlling the formation of diffusion coated layer were the interdiffusion coefficient, aluminum deposition rate, and coating time.
(2-3) The surface aluminum concentration increased with the increase in diffusion coating time and aluminum deposition rate. While, the surface concentration decreased with the increase in interdiffusion coefficient.
(2-4) When the both values of surface aluminum concentrations of a specimen treated under the following two conditions were equal,
(A) (B)
aluminum deposition rate V₁ V₂
interdiffusion coefficient D₁ D₂
diffusion coating time t₁ t₂
there would be a following relationship:
t₁/t₂=(V₂/V₁)²(D₁/D₂)
(3) The results of X. M. A. analysis were as follows:
(3-1) The surface aluminum concentration was slightly lower with the rise of treating temperature.
(3-2) The surface aluminum concentration was slightly lower with the increase of treating time.
(3-3) The surface aluminum concentration of the specimen treated with concentrated HCl gas (in which aluminum deposition rate was higher than that in dilute HCl gas) was higher than that treated with dilute HCl gas.
As described above, the results of calculation correspended well with the experimental results by X. M. A. analysis.

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