抄録
The behavior of corrosion rate in 7.5% HCI aqueous solution of commertial grade zinc sheet rolled up to 90% total reduction under the condition of 3, 5 and 10% reduction per pass, has been investigated by measuring the residual stress and rolling texture by means of X-ray diffraction. In the case of the as-rolled sheet, the corrosion rate indicated a maximum value at 30% total reduction and subsequently a constant value at heavy reductions. In the case of the sheet held for one month at room temperature after cold rolling, the corrosion rate becomes an averaged value for the total reduction and is approximately equal to that of the as-rolled sheet over 40% reduction. The difference of one-pass reduction did not found have any effect on the corrosion rate. The correlation between residual stress and corrosion rate was found. At 30% total reduction, the maximum residual stress generated by twin formation and lattice distortion. Subsequently, the residual stress was released by slip rotation on the basal plane during the rolling over 30% reduction. At heavy reductions, the slip rotation on the basal plane and the twin formation are repeated, and consequently the residual stress shows an approximately constant value.
