Precipitation kinetics of NZ30K-Mg alloys based on electrical resistivity measurement
(Shanghai Key Laboratory of Materials Laser Processing and Modification,
School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China)
School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China)
Abstract: The electrical resistivity of NZ30K-Mg alloy was measured at different heating rates during continuous heating to study the precipitation kinetics. Two kinds of metastable phases, β″ and β′, formed during the heating. Kissinger method and differential isoconversional method were employed to assess the precipitation kinetic parameters of NZ30K-Mg alloy, activation energy Eα and pre-exponential factor . The fraction of transformation (α) and the precipitation sequence in NZ30K-Mg alloy were determined. Continuous heating transformation (CHT) and isothermal heating transformation (IHT) diagrams were further obtained for guiding the aging of NZ30K-Mg alloy. The analysis shows that the precipitation kinetic parameters of NZ30K-Mg alloy can be obtained accurately using isoconversional method.
Key words: NZ30K-Mg alloy; precipitation kinetics; differential isoconversional method; continuous heating transformation; isothermal heating transformation