EFFECT OF INHIBITORS ON THE ELECTROCHEMICAL CONDITIONS AT THE CRACK TIP IN CYCLIC LOADING 40KH STEEL

We examined the effect of inhibitors for neutral electrolytes with various acting mechanisms, on the electrochemical conditions on the surface and in the tip of a corrosion-fatigue crack (CFC). Inhibitors with four different acting mechanisms were added to the medium: passivating inhibitor, i. e. , potassium bichromate (K//2Cr//2O//7) and sodium nitride (NaNO//2); absorbing inhibitor, i. e. , zinc sulfate (ZnSO//4); neutralizing inhibitor, i. e. , sodium tetraborate (Na//2B//4O//7), and an absorbing inhibitor, i. e. , hydrazine (N//2H//4). The inhibitors examined exert different effects on the electrochemical parameters on the surface of the specimen and in the tip of CFC and, consequently, lead to various efficiencies of shielding the steel against corrosion-mechanical failure in distilled water.