Ultrasonic solidification mechanism and optimized application performances of ternary Mg_(71.5)Zn_(26.1)Y_(2.4) alloy  

作　　者：Y.J.Hu J.Y.Wang W.Zhai B.Wei 

机构地区：[1]School of Physical Science and Technology,Northwestern Polytechnical University,Xi’an 710072,China

出　　处：《Journal of Magnesium and Alloys》2023年第10期3829-3839,共11页镁合金学报（英文）

基　　金：financially supported by National Natural Science Foundation of China (nos.52088101 and 52130405);Basic Research Project of Shaanxi Natural Science Foundation (no: 2021JCW-09 and 2023-JC-JQ-28);Key R&D Plan of Shaanxi Province-Key Industrial Innovation Chain Project (no: 2020ZDLGY13-03)。

摘　　要：One dimensional(1D) and three dimensional(3D) ultrasound sources were applied to the solidification process of Mg_(71.5)Zn_(26.1)Y_(2.4) alloy.The acoustic spectra were in-situ measured, based on which the cavitation intensities and dynamic solidification mechanism were further investigated. With the increase of ultrasonic dimension and amplitude, the primary Mg_(3)Zn_(6)Y phase was significantly refined from petals to nearly pentagonal shape. The sound field measurements showed that the transient cavitation played a decisive role in generating a high local undercooling, which facilitated the formation of icosahedral clusters and promoted the nucleation of primary Mg_(3)Zn_(6)Y phase. The morphological transition of(α-Mg+Mg_(3)Zn_(6)Y) eutectic from lamellar to anomalous structure occurred under 3D ultrasonic condition. The stable cavitation took the main responsibility because the high pressure excited by nonlinearly oscillating bubbles induced the preferential nucleation of α-Mg phase rather than Mg_(3)Zn_(6)Y phase. As compared with its static values, the tensile strength and compression plasticity of this alloy were increased by the factors of 1.9 and 2.1, and its corrosion resistance was also improved with the corrosion current density decreased by one order of magnitude.

关 键 词：Three dimensional ultrasounds Quasicrystalline Mg_(3)Zn_(6)Y phase Anomalous eutectic Mechanical performances Corrosion resistance 

分 类 号：TG146.22[一般工业技术—材料科学与工程]