中國有色金屬學報(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 24 No. 7 July 2014 |
（1. Institute of Materials Science and Technology, Vienna University of Technology,
Favoritenstra？e 9-11, 1040 Vienna, Austria;
2. Materials Center Leoben Forschung GmbH, Roseggerstra？e 12, 8700 Leoben, Austria;
3. Christian Doppler Laboratory for Early Stages of Precipitation, Institute of Materials Science and Technology,
Vienna University of Technology, Favoritenstra？e 9-11, 1040 Vienna, Austria）
Abstract:Differential scanning calorimetry (DSC) has been used extensively to study different solid state reactions. The signals measured in DSC are associated with the growth and dissolution of different precipitates during a specific heat cycle. The time-temperature dependence of heat cycles and the corresponding heat flow evolution measured in the sample by DSC provide valuable experimental information about the phase evolution and the precipitation kinetics in the material. The thermo-kinetic computer simulation was used to predict the DSC signals of samples taken from 6xxx and 2xxx alloys. In the model, the evolution of different metastable and stable phases and the role and influence of excess quenched-in vacancies in the early stage of precipitation were taken into account. Transmission electron microscopy (TEM) and high-resolution TEM were used to verify the existence of precipitates, their size and number density at specific points of the DSC curves.
Key words: differential scanning calorimetry; aluminum alloys; precipitation kinetics; simulation; vacancy; MatCalc
