Advanced   Register
IMR OpenIR  > 中国科学院金属研究所  > 期刊论文

题名: Development of low-alloyed and rare-earth-free magnesium alloys having ultra-high strength
作者: Pan, HC;  Qin, GW;  Huang, YM;  Ren, YP;  Sha, XC;  Han, XD;  Liu, ZQ;  Li, CF;  Wu, XL;  Chen, HW;  He, C;  Chai, LJ;  Wang, YZ;  Nie, JF
发表日期: 2018-5-1
摘要: Developing ultra-high strength in rare-earth-free Mg alloys using conventional extrusion process is a great challenge. What is even more difficult is to achieve such a goal at a lower processing cost. In this work, we report a novel low-alloyed Mg-2Sn-2Ca alloy (in wt. %) that exhibits tunable ultra-high tensile yield strength (360-440 MPa) depending on extrusion parameters. More importantly, there is little drop in mechanical properties of this alloy even when it is extruded at a speed several times higher than those used in the reported high strength Mg alloys. Examination of as-extruded microstructures of this Ca-containing Mg alloy reveals that the ultra-high strength is mainly associated with the presence of surprisingly submicron matrix grains (down to similar to 0.32 mu m). The results suggest that the Ca addition promotes accumulations of the pyramidal dislocations, which eventually transform into the low angular grain boundaries (LAGBs). The high number density of LAGBs separate the alpha-Mg matrix via either discontinuous dynamic recrystallization (DDRX) mechanism in the early stage or the continuous dynamic recrystallization (CDRX) mechanism in the later stage of extrusion, which effectively enhances the nucleation rates of the DRXed grains. More importantly, large amount of Ca segregation along LAGBs, accompanied with dynamically precipitated Mg2Ca nano-phases, are detected in the present non-severely deformed samples. It is the combination of solute segregations and numerous Mg2Ca nano-precipitates that contributes to the formation of the ultra-fine grains via pinning mechanism. The ultrafine grains size, Ca enrichment in most LAGBs, and residual Mg2Ca nano-precipitates would in turn contribute significantly to the enhancement of the yield strength of the as-extruded Mg-2Sn-2Ca (wt.%) alloy. The low content of alloying elements and the fast one-step extrusion process render the present alloys low-cost and thus have great potential in large-scale industry applications. (C) 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
刊名: ACTA MATERIALIA
Appears in Collections:中国科学院金属研究所_期刊论文

Files in This Item:

There are no files associated with this item.




Recommended Citation:
Pan, HC,Qin, GW,Huang, YM,et al. Development Of Low-alloyed And Rare-earth-free Magnesium Alloys Having Ultra-high Strength[J]. Acta Materialia,2018,149:350-363.

SCI Citaion Data:
Service
 Recommend this item
 Sava as my favorate item
 Show this item's statistics
 Export Endnote File
Google Scholar
 Similar articles in Google Scholar
 [Pan, HC]'s Articles
 [Qin, GW]'s Articles
 [Huang, YM]'s Articles
CSDL cross search
 Similar articles in CSDL Cross Search
 [Pan, HC]‘s Articles
 [Qin, GW]‘s Articles
 [Huang, YM]‘s Articles
Scirus search
 Similar articles in Scirus
Related Copyright Policies
Null
Social Bookmarking
  Add to CiteULike  Add to Connotea  Add to Del.icio.us  Add to Digg  Add to Reddit 
所有评论 (0)
暂无评论
 
评注功能仅针对注册用户开放,请您登录
您对该条目有什么异议,请填写以下表单,管理员会尽快联系您。
内 容:
Email:  *
单位:
验证码:   刷新
您在IR的使用过程中有什么好的想法或者建议可以反馈给我们。
标 题:
 *
内 容:
Email:  *
验证码:   刷新

Items in IR are protected by copyright, with all rights reserved, unless otherwise indicated.

 

 

Valid XHTML 1.0!
Copyright © 2007-2018  中国科学院金属研究所  -Feedback
Powered by CSpace