Effect of Pulse Frequency and Current Density on Steel Sheet Cleanliness and Hydrogen Permeation

The effect of pulse frequency and current density on the effectiveness of biphasic pulse electrocleaning is discussed. Moderate frequency (5Hz) is found to be more effective than lower or higher frequency on steel surface cleanliness. A novel interpretation of cyclic voltammagrams is used to estimate the surface cleanliness. This correlates very well with XPS determination of surface carbon levels. This result is discussed in terms of mechanisms of electrocleaning. Moderate frequency (5–10Hz) is more effective than lower frequency for inhibiting hydrogen permeation. This method can prevent hydrogen brittleness on the electrocleaning high-strength steel.