含有 LPSO 相和 γ' 析出相的挤压态 Mg-8.2Gd-3.8Y-1.0Zn-0.4Zr（wt.%）合金的时效行为。

Ageing behavior of extruded Mg-8.2Gd-3.8Y-1.0Zn-0.4Zr (wt.%) alloy containing LPSO phase and γ' precipitates.

机构信息

School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, PR China.

Research Center for Advanced Magnesium Technology, Nagaoka University of Technology, Nagaoka 940-2188, Japan.

出版信息

Sci Rep. 2017 Feb 23;7:43391. doi: 10.1038/srep43391.

DOI:10.1038/srep43391

PMID:28230211

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC5322521/

Abstract

The effect of long period stacking ordered (LPSO) phase and γ' precipitates on the ageing behavior and mechanical properties of the extruded Mg-8.2Gd-3.8Y-1.0Zn-0.4Zr (wt.%) alloy was investigated. The results show that more β' phases precipitate during ageing treatment in the LPSO phase containing alloy so that the LPSO phase containing alloy exhibits a higher age-hardening response than the γ' precipitates containing alloy. The precipitation strengthening induced by β' precipitates is the greatest contributor to the strength of the peak-aged LPSO-containing alloys. Higher strength is achieved in γ' precipitates containing alloy due to the more effective strengthening induced by dense nanoscale γ' precipitates than LPSO phases as well as the higher volume fraction of coarse unrecrystallized grains with strong basal texture. The extruded alloy containing γ' precipitates after T5 peak-ageing treatment shows ultra-high tensile yield strength of 462 MPa, high ultimate tensile strength of 520 MPa, and superior elongation to failure of 10.6%.

摘要

研究了长周期堆垛有序（LPSO）相和 γ' 析出相在挤压 Mg-8.2Gd-3.8Y-1.0Zn-0.4Zr（wt.%）合金时效行为和力学性能中的作用。结果表明，在含有 LPSO 相的合金时效处理过程中会析出更多的β'相，因此含有 LPSO 相的合金表现出比含有γ'相的合金更高的时效硬化响应。β'析出相引起的析出强化是峰值时效 LPSO 相合金强度的最大贡献者。由于密集纳米级 γ'析出相比 LPSO 相以及具有强基面织构的未再结晶粗晶粒的更高体积分数引起的更有效的强化，含有 γ'相的合金具有更高的强度。经过 T5 峰值时效处理的含有γ'相的挤压合金表现出超高的拉伸屈服强度 462 MPa、高的拉伸强度 520 MPa 和出色的断裂伸长率 10.6%。