Electrochemical Determination of Hydrogen Entry to HSLA Steel during Pickling

Abstract

Pickling with hydrochloric acid is a standard method to clean steel surfaces before hot-dip galvanizing. When normal low strength steels are pickled, hydrogen formed in pickling reactions does not have any significant harmful effect on the mechanical properties of steel. However, in pickling of steels with higher strength, the penetration of hydrogen into the steel may cause severe damages.e effect of pickling of high-strength low-alloy (HSLA) steels was investigated using a cell construction based on the DevanathanStachurski method with modified anodic surface treatment and hydrogen production using acid. e penetration and the permeability of hydrogen were measured using an electrochemical cell with hydrochloric acid on the one side of the steel sample and a solution of NaOH on the other side. No protective coating, for example, palladium on the anodic side of the sample, is needed. e penetration rate of hydrogen into the steel and exit rate from the steel were lower for higher strength steel.

Combining Electrochemical and Theoretical Analysis to Evaluate Hydrogen Permeation Inhibitors During Free Corrosion

“…Hydrogen permeation during free corrosion of the steels in HCl and H 2 SO 4 solutions was determined in the presence and absence of inhibitors, using a D-S type cell 6,32 (Figure 2).…”

“…The detection side employed 0.2 mol L -1 NaOH solution, which is a commonly used alkaline solution 6 . On this side, atomic hydrogen was performed by anodizing the steel at 0.0 V (vs. Ag|AgCl|KCl sat ).…”

“…Steel structures can suffer from severe damage, such as brittle fracture, due to the absorption of hydrogen atoms [1][2][3] . Hydrogen can also penetrate the steel crystal lattice or lattice defects during acid cleaning, leading to embrittlement [4][5][6] . In many industries, hydrochloric or sulfuric acids are used at concentrations up to 20% in pickling processes to remove scale and in oil well acidizing, with organic inhibitors being used to prevent corrosion of steel 1,2,[7][8][9][10] .…”

“…However, it is not guaranteed that these inhibitors can also function as hydrogen permeation inhibitors [11][12][13][14] . Moreover, there is a lack of systematic experimental studies investigating the effect of organic inhibitors on acid pickling corrosion 11,15,16 , while even fewer studies have addressed hydrogen permeation inhibition 4,6,17 .…”

“…In recent work 6 , the authors used a modified Devanathan-Stachurski (D-S) cell, where loading of hydrogen occurred during freely corroding steel dissolution in a pickling process employing a high concentration of hydrochloric acid (16.5%). In another study 24 the authors designed a device to assess hydrogen permeation into steel during free corrosion in marine environments.…”