| 引用本文: | 李伟,马幼平,杨蕾,张宝林,袁战军.离心压力和冷却速度对AZ91镁合金凝固组织的影响[J].材料科学与工艺,2015,23(6):125-128.DOI:10.11951/j.issn.1005-0299.20150623. |
| LI Wei,MA Youping,YANG Lei,ZHANG Baolin,YUAN Zhanjun.Effect of centrifugal pressure and cooling rate on solidification microstructure of AZ91 alloy[J].Materials Science and Technology,2015,23(6):125-128.DOI:10.11951/j.issn.1005-0299.20150623. |
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| 摘要: |
| 旨在优化AZ91镁合金凝固组织,通过OM和XRD设备研究了不同离心压力和冷却速度对AZ91镁合金凝固组织演变的影响,结果表明,随着离心压力的增大,合金晶粒尺寸细化,第二相β(Mg12Al17)析出量减少,不保温试样,β相形态由粗大连续网状向细小断续状转变,保温试样,β相为粒状弥散分布晶内,压力增大,颗粒数量减小,粒径细化.同等凝固压力下,增大冷速,一次β相析出量增多,二次β相析出量减少.XRD分析表明,增大离心压力β相峰值略微减弱,α-Mg的晶格常数减小. |
| 关键词: 离心压力 冷却速度 AZ91镁合金 凝固组织 |
| DOI：10.11951/j.issn.1005-0299.20150623 |
| 分类号:TG146.22 |
| 基金项目:基金项目:陕西省工业攻关项目(2014K08-16)；陕西省教育厅专项科研计划项目(14JK1411)；陕西省社发重点合作单位项目(2012KTJD02-01). |
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| Effect of centrifugal pressure and cooling rate on solidification microstructure of AZ91 alloy |
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LI Wei, MA Youping, YANG Lei, ZHANG Baolin, YUAN Zhanjun
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(Dept. of Metallurgical Engineering,Xi′an University of Architecture and Technology,Xi′an 710055,China)
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| Abstract: |
| Solidification microstructure evolution of magnesium alloy AZ91 under different centrifugal pressure and cooling rate were explored through OM and XRD to optimize solidification microstructure of AZ91 alloy , With the increasing of centrifugal pressure, the grain size and precipitation of second phase β-Mg12Al17 was decreased, the morphology of β turned from coarse continuous networks to thin interruption in the sample without heat preservation, while in the sample with heat preservation, granular β phase distributed within the grains. The number of β was reduced ,and the size of β was refined with increasing centrifugal pressure. With the increase of cooling rate under same pressure, more primary β precipitated, but less secondary β precipitated. Result of XRD showed that the peak value of β weakened slightly and the lattice constant of α-Mg decreased with increasing pressure. |
| Key words: centrifugal pressure cooling rate AZ91 magnesium alloy solidification microstructure |
