The continuous observations of cracking in stress corrosion have been conducted on the α/β brass.
It was shown that the cracks were originated at the phase-boundary or the β-phase, though were not observed in β-grains.
It was considered that the edge dislocations might be piled up between slip planes owing to the increment of interaction, as the effect of increase of zinc content, among the dislocations and the solute atoms, or at the phase boundary as an obstacle against edge dislocations according to the following relation:
σknbG≈BT
The stress corrosion strain curves followed in the general creep rules.

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Long term fundamental tests were carried out concerning the anode behavior of various grades of zinc in the synthetic sea-water at room temperature. The results obtained were as follows:
(1) Under an anodic current (1mA/cm²), the anode potential of some grades of zinc became catholic with the lapse of time. While, in the case of special high-grade zinc (approx. 99.99% and 99.995% pure), the potential of -0.95- -1.0V (referred to sat. calomal) were fully maintained.
(2) Liniar relations were clearly observed between the degree of increase of anode potential and the output current efficiency or the rate of self-corrosion.
(3) The effect of amalgamation which decrease the anodic polarization were confirmed only in the case of high-grade zinc.

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