The Experimental Investigation Of Stress Corrosion For37CrNi3MoVe Steer In Artificial Seawater

Underwater high pressure vessels are widely used in shipbuilding industry, and the stress corrosion failure causes major economic losses and even catastrophic accidents.37CrNi3MoVE steel is the steel used in underwater high pressure vessels, so there will be important significance to research the stress corrosion of37CrNi3MoVE steel in artificial seawater.37CrNi3MoVE steel is chosen as the research object in this paper, and the slow strain rate test(SSRT), constant displacement loading test of compact tensile(CT) and constant displacement rate loading test of compact tensile(CT) are adopted to study the stress corrosion in artificial seawater. Accoding to the data of tests, we get stress corrosion threshold stress intensity factor and stress corrosion crack growth rate in different loading mode. Then we discuss the critical crack size of37CrNi3MoVE steel vessels (D=465mm, t=17. lmm) under the working pressure (P=40MPa).The main work and research results are as follows:(1) Through the slow strain rate test, we get the stress-strain curses of37CrNi3MoVE steel in the enviorenment of the air and artificial seawater.(2) Constant displacement experiments measured that stress corrosion critical stress intensity factor (Kiscc) is108MPa?(?) under different initial stress intensity factors (Ki).(3) Constant displacement rate experiments also measured that stress corrosion critical stress intensity factor (K1scc) is108MPa?(?) under different displacement rates, and got da/dt-K1curves to analysis. (4) In artificial seawater, the critical crack size of37CrNi3MoVE steel cylinders (D=465mm, t=17.1mm) under the working pressure (P=40MPa) is5.578mm.