Hydrogen Evolution on Beta III Titanium Alloy

Abstract The rate of hydrogen evolution on Beta III titanium alloy in 1.0, 2.5, 5.0, 7.5, and 10.0 N sulfuric acid at 23, 45, 60, and 75 C (73, 113, 140, and 167 F) has been investigated. The cathodic Tafel slopes were 60, 64, 67, and 70 mV, respectively, at each temperature. The reaction order was first order with respect to the concentration of hydrogen ions. The chemical recombination mechanism for the hydrogen evolution reaction using the Temkin adsorption isotherm with activated heat of adsorption is consistent .with the experimental data. The corrosion rate increased with increase in both acid concentration and temperature. The activation energies for corrosion were 22.1, 20.8, and 19.3 kcal/mole for corrosion in 1.0, 2.5, and 5.0 N H2SO4, respectively, and 15.9 kcal/mole in 7.5 and 10.0 N H2SO4.