The processes taking place during supersaturation of the Al-4.7mass%Cu alloy have been studied by the methods of quantitative metallography and dilatometry. The grain growth activation energy was about 95 kJ/mol, and the exponent of time, n, was close to 0.4. Dissolution of precipitates caused two-stage shrinkage of the sample, which had activation energies of 90 kJ/mol (first stage, n=0.8) and 63 kJ/mol (second stage, n=0.4). The kinetics of the phase transformation during aging of the Al-4.7mass%Cu alloy has been studied by the dilatometry and differential thermal analysis The activation energy of the precipitation processes within the range of 50–320 °C varied between 50 and 100 kJ/mol and confirmed the results obtained previously. For the precipitation processes within the range of 320–462 °C, the activation energy varied from 226 to 300 kJ/mol. The results obtained were compared with literature data with good agreement.