The influence of a 700G magnetic field was investigated using baths containing cobalt sulfate, nickel sulfate or a mixture of the two for electrolytic coloring of the anodic oxidation coatings on aluminum formed in baths of H₂SO₄ or NaOH-H₂O₂. By measuring, in the presence of a magnetic field, the reflection absorption spectra of electrolytic colored film formed in nickel bath, it was possible to observe a high reflection absorbance at longer wavelengths.
Magnetic hysteresis curves showed a higher residual magnetic flux density and coercive force than in the case of nonmagnetic fields. In DC and AC electrolysis at constant voltage, the electrolytic current was increased by the effect of a magnetic field. It is considered that electrolytic current was induced by the magnetic force, and acted to enhance the electrolytic reduction of metallic ions in the bath. These results indicate that electrolytic deposition of metal in the pores was affected by the Lorentz's force and enhanced in the presence of a 700G magnetic field.

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Bonding of the molybdenum was carried out by immersion in fused mixture of boric acid, potassium borate, magnesium powder and an activator. In this process, boron supplied by the fused boric acid and potassium borate formed a boride layer on the molybdenum surface. The composition, structure, thickness, and hardness of the molybdenum boride, and the wear resistance of the bonded molybdenum were investigated. X-ray analysis showed that the composition of the molybdenum boride layers formed by immersion boriding were MoB (δ-MoB) and Mo₂B₅. Boride layers formed by immersion at 1000°C for 5h were about 25μm thick, and had knoop hardness numbers of from 2900 to 3400. The apparent activation energy obtained was 80.1kcal/mol for the formation of molybdenum boride at temperatures from 900 to 1000°C. Borided molybdenum showed greater wear resistance than did unborided molybdenum within the limits of this experiment.

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Multicomponent films of TiN and Fe with various composition ratios (TiN/Fe=x/y (vol)) were deposited on steel substrates by RI sputtering using a single generator, the power from which was split by variable coupling capacitors and applided to TiN and Fe targets. Hard multicomponent films of TiN and Fe were made to improve adhesion to the steel substrate.
The adhesion of films on the steel substrates was measured by a scratch tester.
Specimens with a series of TiN/Fe ratios (0/10, 2/8, 4/6, 6/4, 8/2, 10/0) were obtained by changing voltage under a constant argon-plus-nitrogen pressure of 1.3Pa.
Film composition was measured by x-ray diffraction and EPMA.
The results show that multicomponent TiN/Fe films were homogeneous, and adhesion to the steel substrates was the same that of single-component TiN films.

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A study was made of the effects of composition and plating conditions on the elements codeposited in chromium deposits from chromium sulfate (III)-potassium formate baths.
It was shown that the carbon content of the chromium deposits as 1.6-4.8wt%. The as-plated hardness of the chromium deposits was about Hv 670, but the deposits were herdened by heat treatment as aging temperature increased, up to 700°C, at which point a maximum value was reached about Hv 1650.

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Steel sheet hot-dip coated with an Al-Zn eutectoid-base alloy having a fine-grained structure has been tested, and the proper coating condition and some properties of the coated steel have been studied. There exists a bath temperature (T_S) at which the thickness of the coating becomes minimum. The coating deposited from a bath containing only the Al-78 Zn alloy is very brittle, and this is believed to be due to a rapid growth of a brittle alloy-phase reacted with Fe diffused from the steel substrate. Coatings dipped at temperatures around T_S from an Al-78 Zn bath to which was added about 0.1 to 0.3wt. % Si showed good formability, coating adhesion and flaking behavior, corrosion resistance, and damping capacity. The film had a fine, equi-axial structure that has a favorable effect on superplasticity and damping of vibration.

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The influence of annealing atmosphere upon oxidation and descaling was studied to determine the annealing atmosphere most conducive to the descaling of stainless steel. Cold rolled SUS 430 and SUS 304 were annealed in a siliconit furnace which was set to 870°C and 1, 150°C, respectively, and which was filled with the exhaust gases generated from the burning of propane. The annealing atmosphere was changed by controlling the ratio of propane and air, and descaling was done by anodic electrolysis (4.0A/dm², 80°C, 40sec) in a solution of Na₂SO₄ (200kg/m³, pH: 6.2). Specimens were then pickled in HNO₃-HF solution (14%-4%, 7%-2%) at 20°C or 60°C for 10sec. In SUS 430, the Cr depletion profile and descaling behavior varied with changes in the annealing atmosphere because the rate-determining step of oxidation was the diffusion of Cr through the oxide scale, whose composition and diffusion velocity of Cr was changed by the annealing atmosphere. Descaling of SUS 430 was very easy when it had been annealed in an atmosphere containing CO (carbon monoxide) or 0.2% O₂ and was relatively difficult when the annealing atmosphere containing over 1% O₂. In SUS 304, the Cr depletion profile was not changed by the annealing atmosphere because the rate-determining of oxidation was diffusion of Cr in the matrix, but the composition of oxide scale was changed depending on whether CO was contained in the atmosphere or not. Descaling was very difficult when SUS 304 had been annealed in an atmosphere containing CO, but was relatively easy when annealed in an atmosphere containing O₂.

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