Simulation and Computation of Isothermal Precipitation Kinetics and Precipitation Strengthening for AA6061 Aluminum Alloy

doi:10.3901/JME.2021.20.126

Abstract

Abstract: The Kampmann-Wagner Numerical (KWN) model is used to simulate and calculate the precipitation kinetics behavior of AA6061 aluminum alloy during isothermal ageing at 190℃, 210℃ and 225℃. Evolution laws of particle size distribution, particle number density and precipitate volume fraction are obtained. The model can accurately predict the inflection point of particle size and precipitate volume fraction evolution when ageing enters coarsening period. Combined with isoconversional method, experimental result of differential scanning calorimetry(DSC) at different heating rate is used to obtain the precipitation reaction progress curve, which is in good agreement with the calculation result. Yield strength evolution during isothermal ageing is calculated using precipitation strengthening model and the calculation method proposed here is validated by comparing with the yield strength converted from the measured hardness.

Key words: AA6061 aluminum alloy, isothermal ageing, precipitation kinetics, KWN model, precipitation strengthening simulation

CLC Number:

TG156

CHEN Zhenhao, XU Jun, LIU Qingdong, LI Chuanwei, GU Jianfeng. Simulation and Computation of Isothermal Precipitation Kinetics and Precipitation Strengthening for AA6061 Aluminum Alloy[J]. Journal of Mechanical Engineering, 2021, 57(20): 126-132.

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