In this study, it was attempted to examine the properties of electrodeposited silver-copper alloys for contact materials.
The results obtained were as follows:
(1) The adhesive property of electrodeposited silver-copper alloy to substrate pure copper was almost in the same degree as that of the deposit in silver plating.
(2) It was found that silver was co-existent with copper by X-ray diffraction in the plated layers containing 20-96% of Cu.
(3) The maximum microhardness of the deposited alloys attained to about Hv 160.
(4) The wear resistance of the deposited alloys was higher than that of silver plated surface.
(5) The contact resistance of the deposited alloys was not higher than that of the deposit in silver plating.

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The relation between the plating rate and the bath conditions were studied on electroless cobalt plating baths containing hydrazine as a reducing agent, and the properties of the deposited film were investigated in comparison with those from the baths containing hypophosphite.
The following results were obtained.
1. Caustic alkaline tartrate bath was selected for a suitable bath having a relatively large plating rate and a good stability, and its optimum conditions were as follows:
CoCl₂ 0.05-0.08mol/l Thiourea 2-4ppm
N₂H₄⋅2HCl 1.0mol/l pH 12.0(NaOH)
Na-tartrate 0.4mol/l Bath temperature 90°C
2. The appearance of the deposit was bright when the thickness of the film was less than about 2μ, but it changed to be dull when the film was thicker. The surface state became more deteriorated with the increase of film thickness.
3. It was found that the deposit consisted of α-cobalt polycrystals, being the same as the deposit from hypophosphite baths. However, the grain size of the present deposit was in the range of 200-400Å which was larger than that from hypophosphite baths (100-200Å).
4. It was also found that the deposit was a ferromagnetic substance having coercive force (H_c) of about 100oe., maximum magnetic flux density (B_s) of 11, 000-13, 000 gauss, and squareness (B_r/B_s) of 0.4.

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Physical, mechanical, and electrical properties of flame-sprayed barium titanate coatings were considerably affected by heat treatment.
Micro-crystallites were developed with the elevation of annealing temperature. The structure of crystallites changed to tetragonal system at 1, 400°C. The effects of the substrate on the crystallites structure was remarkable in rod sprayed coatings. The structure of the coatings with substrate annealed at 1, 400°C turned into tetragonal system, whereas in case of the structure without the substrate annealed at that temperature still remained in cubic system.
The bond strength increased with the elevation of annealing temperature up to 1, 200°C.
The surface roughness after heat treatment reached its maximum at 1, 400°C. The dielectric constant and dissipation factor proportionally increased with the elevation of annealing temperature. Furthermore, the dependence of properties on the temperature more increased at higher annealing temperature.
The breadth of the peak of Curie point increased as compared with that of ceramic barium titanate when heat treated at above 1, 200°C (in rod-spraying) or above 1, 000°C (in powder-spraying).
When the annealing temperature was higher, the insulation resistance was lower; however, the dependence of the resistance on the temperature was less.

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