THE EFFECT OF COLD WORK AND DISSOLVED HYDROGEN IN THE STRESS CORROSION CRACKING OF ALLOY 82 AND ALLOY 182 WELD METAL

摘要

Alloy 182 and Alloy 82 V-groove welds were tested in a hydrogenated water environment using compact tension specimens to determine the stress corrosion cracking growth rates of these materials. The Alloy 82 weld was also cold rolled to a 12% reduction in thickness to increase yield strength. Alloy 182 crack growth rates were found to be approximately the same as the Alloy 82 welds tested in this study, but in agreement with literature data. The SCC growth rates were found to depend on the yield strength/cold work, where SCC rates were higher in the cold worked welds than in the as-welded condition. The effect of orientation on crack growth was less than a factor of 2. SCC growth rates were also found to increase when the dissolved hydrogen concentration was decreased from 50 cc H_2/kg H_2O to 26 cc H_2/kg H_2O at 338℃. Engagement-corrected SCC growth rates show that the stress dependence for growth in the welds was approaching that of wrought alloys.