Abstract
An electrolytic solution containing 1% NaCl-3 to 5% EDTA solution is used as a new electrolyte in the electrolytic isolation for the metallographic analysis of steel.
The steel sample, which is covered with filter paper, is connected as an anode, and is dissolved in 100ml of NaCl-EDTA electrolyte at current density of 50mA/cm2 for 2 to 4hr. A residue of carbide, nitride, oxide and other impurities can be collected in the filter paper, and is separated and analyzed by a chemical procedure as directed in previous papers. To the electrolyte, HNO3, HClO4 and H2SO4 are added, subsequently, it is evaporated to dense white fumes, and then the elements as solid solution are determined by a photometric method. Quantitative recovery of sulfides in carbon steel is obtained by use of NaCI-EDTA electrolyte.
