Mechanical properties and structural stability of a bulk nanostructured metastable aluminum-magnesium system
Mechanical properties and structural stability of a bulk nanostructured metastable aluminum-magnesium system
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DOI：
10.1016/j.msea.2020.140050
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发表时间：
2020-10
期刊：
影响因子：
6.4
通讯作者：
Jae-Kyung Han;K. Liss;T. Langdon;J. Jang;M. Kawasaki
中科院分区：
文献类型：
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作者：
Jae-Kyung Han;K. Liss;T. Langdon;J. Jang;M. Kawasaki
研究了高压扭转（HPT）诱导的块体纳米结构亚稳Al-Mg合金在室温自然时效60 d后的力学性能和结构稳定性。样品表现出1.3-1.5 GPa的高屈服强度，通过实现0.036的高应变速率敏感性，具有优异的塑性。高硬度是由于晶粒细化和固溶强化的共同贡献。X射线衍射分析显示，由于加工后Al基体中Mg的过饱和，具有约0.0202的高成分显微应变。由于过饱和Mg溶质的不均匀分布而没有任何第二相的成核，该微应变在自然老化后增加到~0.0274，从而证明了合理的结构稳定性。
The mechanical properties and structural stability of a high-pressure torsion (HPT)-induced bulk nanostructured metastable Al–Mg system were examined after natural aging at room temperature for 60 days. The sample demonstrated a high yield strength of 1.3–1.5 GPa with an excellent plasticity by achieving a high strain rate sensitivity of 0.036. The high hardness is attributed to the concurrent contributions of grain refinement and solid solution strengthening. An X-ray diffraction analysis revealed a high compositional microstrain of ~0.0202 due to the supersaturation of Mg in the Al matrix after processing. This microstrain increased to ~0.0274 after natural aging due to the heterogeneous distribution of supersaturated Mg solutes without any nucleation of a second phase, thereby demonstrating a reasonable structural stability.