Corrosion potential measurements, voltammetric techniques and electrochemical impedance have been used to evaluate the corrosion resistance of M2 high speed steel in aqueous solutions containing chloride, bromide, iodide, nitrate, sulfate and perchlorate salts of sodium and potassium of varying concentration. The influence of changing the cation was found to be small and an order of anion aggressivity was established as : sulfate > chloride > bromide > perchlorate > iodide > nitrate. The data obtained are important for the diagnosis, prediction and analysis of corrosion processes due to the breakdown of sputtered coatings on M2 steel in diverse environments.