摘要
The long and short fatigue crack growth (FCG) behavior of 12CrNi3MoV (S1) and 10CrNi5MoV(S2) steel was investigated at cathodic protection in 3.5 % NaCl solution and artificial seawater. The results indicate that long and short FCG show different behavior at cathodic protection. Short FCG is apparently hindered at appropriate cathodic protection potential (-900 mV SCE) and accelerated at over protection potential(-1200 mV SCE). Cathodic protection increases long FCG rate, and the more negative the cathodic protection potential, the greater the long FCG rate. At the same amplitude of stress intensity ( ΔK ), short FCG rate is greater than the long one and their difference becomes less at cathodic protection. The FCG rate in 3.5 % NaCl solution is greater than in artifitial seawater. The FCG rate of S2 steel is bigger then that of S1 steel. The FCG rate of weld bond of S2 steel is lower than that of parent metal and weld beam. In above cases, the anode dissolution, the wedging of corrosion products or deposit and hydrogen embrittlement in long and hort crack tip are also discussed.
The long and short fatigue crack growth (FCG) behavior of 12CrNi3MoV (S1) and 10CrNi5MoV(S2) steel was investigated at cathodic protection in 3.5 % NaCl solution and artificial seawater. The results indicate that long and short FCG show different behavior at cathodic protection. Short FCG is apparently hindered at appropriate cathodic protection potential (-900 mV SCE) and accelerated at over protection potential(-1200 mV SCE). Cathodic protection increases long FCG rate, and the more negative the cathodic protection potential, the greater the long FCG rate. At the same amplitude of stress intensity ( ΔK ), short FCG rate is greater than the long one and their difference becomes less at cathodic protection. The FCG rate in 3.5 % NaCl solution is greater than in artifitial seawater. The FCG rate of S2 steel is bigger then that of S1 steel. The FCG rate of weld bond of S2 steel is lower than that of parent metal and weld beam. In above cases, the anode dissolution, the wedging of corrosion products or deposit and hydrogen embrittlement in long and hort crack tip are also discussed.
