Study on slow strain rate tensile properties of tower tube steel in simulated ocean environment

The influence of stretch rate, the concentration of the NaCl solution and the temperature in the solution on the stress corrosion cracking of Q345 steel for offshore wind turbine tower was investigated by means of the slow strain rate tensile test. The experimental results show that the stress corrosion susceptibility of Q345 steel in NaCl solution tends to increase monotonically with the decrease of the tensile rate. When the tensile rate is 4×10-7 s-1, the specimen has undergone stress corrosion cracking. The environmental medium greatly reduces the tensile strength, total strain and fracture energy of the Q345 steel. And the sensitivity of stress corrosion cracking of Q345 steel increases with the increase of NaCl concentration. The effect of temperature on the stress corrosion susceptibility of the material is large, and the sensitivity index increased significantly with the increase of temperature. When the temperature is 50℃, it has obvious stress corrosion tendency. © 2020, Solar Energy Periodical Office Co., Ltd. All right reserved.