Superplastic deformation of hydrogenated Ti–6Al–4V alloys

Superplastic deformation behavior of hydrogenated Ti–6Al–4V alloys was investigated at an extensive hydrogen concentration. The superplastic elongation was studied in detail. The microstructures before and after deformation were both observed. Hydrogen enhances superplastic elongation at some certain deformation temperatures, strain rates, and hydrogen concentrations. Hydrogen decreases optimum superplastic temperatures and increases optimum superplastic strain rate. The calculated result of activation energies indicates that hydrogen did not change the superpalstic deformation mechanism. The variation of elongation is attributed to the microstructures of hydrogenated alloys, which are more sensitive to strain rate and temperature in the process of superplastic deformation.