Exceptional grain refinement in a Mg alloy during high pressure torsion due to rare earth containing nanosized precipitates
Exceptional grain refinement in a Mg alloy during high pressure torsion due to rare earth containing nanosized precipitates
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由于含有稀土的纳米级沉淀物，镁合金在高压扭转过程中晶粒异常细化
DOI：
10.1016/j.msea.2018.05.021
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发表时间：
2018-06
期刊：
影响因子：
6.4
通讯作者：
Starink M J
中科院分区：
文献类型：
--
作者：
Sun W T;Qiao X G;Zheng M Y;He Y;Hu N;Xu C;Gao N;Starink M J
通过对固溶时效Mg-8.2Gd-3.8Y-1.0Zn-0.4Zr（wt%）合金的高压扭转（HPT）变形研究，详细研究了纳米稀土（RE）析出相对大塑性变形过程中晶粒细化的影响。在HPT变形的早期阶段，含纳米稀土的β′相促进了位错的产生和堆积。随着应变的增加，析出相被运动的位错切割，并在位错作为溶质原子扩散通道的辅助下逐渐溶解到α-Mg基体中。HPT 2圈后，硬度达到最大值，进一步变形，硬度降低，但组织继续细化，位错密度增加。这是由于沉淀物的持续溶解，其主导了该阶段的硬度演变。HPT 16圈后，析出物几乎完全溶解，平均晶粒尺寸为~33 nm，这是Mg基或Al基合金有史以来报道的最小晶粒尺寸。本发明的峰值时效Mg-8.2Gd-3.8Y-1.0Zn-0.4Zr（wt%）合金在HPT处理期间与铸造和固溶的Mg-Gd-Y-Zn-Zr合金相比表现出相当不同的显微组织演变和硬化行为。
The influence of the nanosized rare earth (RE) containing precipitates on grain refinement during severe plastic deformation is investigated in detail through a study of high pressure torsion (HPT) processing of a solution treated and aged Mg-8.2Gd-3.8Y-1.0Zn-0.4Zr (wt%). In the early stages of HPT deformation, dislocation generation and pile-up is promoted by the nanosized RE containing β′ precipitates. With increasing strain, the precipitates are cut by the moving dislocations and gradually dissolve into the α-Mg matrix aided by dislocations serving as diffusion channels for solute atoms. After HPT for 2 turns, the hardness reaches a maximum and on further deformation the hardness decreases although the microstructure refinement continues and the dislocation density is increasing. This is due to the continuing dissolution of precipitates, which dominates the hardness evolution at this stage. After HPT for 16 turns, the precipitates have almost completely dissolved and the average grain size is ~33 nm, which is the smallest ever reported for a Mg- or Al-based alloy. The present peak-aged Mg-8.2Gd-3.8Y-1.0Zn-0.4Zr (wt%) alloy exhibits quite different microstructure evolution and hardening behaviour during HPT processing as compared to both the cast and the solutionized Mg-Gd-Y-Zn-Zr alloy.
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时效%20行为%20of%20挤压%20Mg—8.2Gd—3.8Y—1.0Zn—0.4Zr%20(wt.%)%20合金%20含%20LPSO%20相%20和%20γ%20—析出物
影响因子：
4.6
作者：
Xu C;Nakata T;Qiao XG;Zheng MY;Wu K;Kamado S
通讯作者：
Kamado S
稀土元素Gd和Y对镁合金固溶强化的影响
影响因子：
6.2
作者：
Gao, L.;Chen, R. S.;Han, E. H.
通讯作者：
Han, E. H.
DOI：
10.1016/j.msea.2003.12.071
发表时间：
2004-12
影响因子：
6.4
作者：
Mayumi Suzuki;T. Kimura;J. Koike;K. Maruyama
通讯作者：
Mayumi Suzuki;T. Kimura;J. Koike;K. Maruyama
DOI：
10.1201/9781420041910.ch12
发表时间：
1984-12
期刊：
Encyclopedic Dictionary of Archaeology
影响因子：
--
作者：
Hamidreza TORBATI-SARRAF;S. Niverty;Rajhans Singh;D. Barboza;Vincent de Andrade;Pavan Turaga;
通讯作者：
Hamidreza TORBATI-SARRAF;S. Niverty;Rajhans Singh;D. Barboza;Vincent de Andrade;Pavan Turaga;
影响因子：
6.2
作者：
B. Smola;I. Stulikova;J. Pelcová;B. Mordike
通讯作者：
B. Smola;I. Stulikova;J. Pelcová;B. Mordike