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The electrochemical reduction of Cr(III) methanesulphonate complexes were investigated on the lead electrode. The Cr(III) electroreduction process proved to be irreversible. The standard rate constants as well as the standard electrode potentials of Cr(III) ions in methanesulphonic acid (MSA) solution are less than those corresponding to the perchlorate electrolytes.

A new aqueous sulfate trivalent chromium bath is described. The chromium bath contains formic acid and carbamide as complexing agents. Chromium was deposited at a temperature of 30÷40 oC and a cathode current density of 10÷25 A dm-2. The bath allows obtaining thick (up to several hundred micrometers) hard chromium coatings with nanocrystalline structure. The electrodeposition rate reaches 0.8÷0.9 µm min-1.