在线提供 19 October 2023
In
this study, the tensile creep behavior of a hot-rolled Mg-4Y-3.5Nd
alloy subjected to different prior thermo-mechanical treatments was
investigated at 220 ℃. Five groups of samples were prepared using
different combinations of the solid solution (S), aging treatment at 220
℃ for 30 h (A), and hot compression at 490 ℃ to a true strain of 0.25
(C). The abbreviations for the samples are S, SA, SC, SAC, and SCA. Upon
examining the yield strength and creep resistance, it was found that
creep resistance could not be directly predicted by the yield strength.
The stability of the deformation bands (DBs) induced by prior
thermo-mechanical treatment plays an important role in determining the
creep resistance. The dislocation of the DBs and demonstrated the best
creep resistance in the SAC sample, which were prepared using a solid
solution, aging treatment, and subsequent hot compression. However,
despite the highest yield strength, frequent dislocation motions
destroyed the stability of the DBs and deteriorated the creep resistance
of the SCA sample, which were prepared using a solid solution, hot
compression, and subsequent aging treatment. Among the thermo-mechanical
treatments used in this study, the application of aging treatment was
important to obtain the resultant creep resistance. When the aging
treatment was performed prior to hot compression, the creep resistance
could be further enhanced based only on hot compression. Accordingly,
the sequence from the strongest to the weakest creep resistance was SAC
> SC > S > SCA > SA.
