Mn 元素对高纯Mg-3Al 合金晶粒尺寸的影响.pdf

文档介绍：第 20 卷第 8 期中国有色金属学报 2010 年 8 月
The Chinese Journal of Nonferrous Metals Aug. 2010
文章编号:1004-0609(2010)08-1495-06

Mn 元素对高纯 Mg-3Al 合金晶粒尺寸的影响

王春建,金青林,周荣,蒋业华

(昆明理工大学材料科学与工程学院,昆明 650093)

摘要:研究 Mn 元素对高纯 Mg-3Al(质量分数,%)合金晶粒尺寸的影响。结果表明:当合金中的 Mn 元素含量
小于 %(质量分数)时,合金的晶粒尺寸变化不大;但当 Mn 元素含量大于 %时,Mn 元素的存在则使合金
的晶粒尺寸迅速增大;Mn 元素的作用主要与影响熔体中含碳晶核的形核能力有关;当 Mn 元素的含量小于其溶
解度时,Mn 元素对含碳晶核的形核能力影响不大,但当 Mn 元素的含量达到或超过其溶解度时,Mn 元素对含碳
晶核的影响迅速增大,最终导致含碳晶核的形核能力降低,引起晶粒粗化。
关键词:镁合金;Mn;晶粒细化;异质形核
中图分类号:TB31 文献标志码:A

Effect of Mn on grain size of high-purity Mg-3Al alloys

WANG Chun-jian, JIN Qing-lin, ZHOU Rong, JIANG Ye-hua

(Faculty of Material Science and Engineering,
Kunming University of Science and Technology, Kunming 650093, China)

Abstract: The effect of Mn on the grain size of high-purity Mg-3Al (mass fraction, %) alloys was investigated. The
results show that the grain sizes of high-purity Mg-3Al alloys changes little when the Mn content is lower than %
(mass fraction), while the grains are coarsened when Mn content is higher than %. The effect of Mn is relative to the
heterogeneous nucleation of carbon-containing cores in the melt. When Mn content is low and dissolves into the melt, the
nucleating potent of carbon-containing cores would not be influenced basically. But when Mn content in the melts is
close to