932. アルコールーヨウ素溶液中Zrの歪電極特性と応力腐食割れ感受性への水添加効果

抄録

The effects of addition of water on the strain-electrode characteristic and stress corrosion susceptibility of Zr were investigated by the electrochemical method using a bending strainelectrode. Test pieces were heat-treated at 1, 073K for 7.2ks, quenched into ice-water and tested under bending strain in CH₃OH-0.33W/0 I containing water.
Rest potential of Zr had a peak in the solution containing 2-3×10^-2V/0 water. In this case, many stress corrosion cracks were observed. An addition of water to the solution progressively increased the rest potential of Zr. The large amount of water, moreover, prevented stress corrosion cracking.
Analysis of fracture mechanics for interpreting stress corrosion cracking, shows that crack velocities have the power law on the stress intensity factor K. Time to fracture of stress corrosion was estimated by parameters C and n controlling the growth of stress corrosion cracks.