The role of Ca,Al and Zn on room temperature ductility and grain boundary cohesion of magnesium

作     者：Supriya Nandy Shao-Pu Tsai Leigh Stephenson Dierk Raabe Stefan Zaefferer 

作者机构：Max-Planck Institut für EisenforschungDüsseldorf 40237Germany 

出 版 物：《Journal of Magnesium and Alloys》 (镁合金学报（英文）)

年 卷 期：2021年第9卷第5期

页      面：1536-1551页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：the financial support by the international doctoral school IMPRS Surmat 

主　　题：Magnesium–Calcium–Zinc alloys Ductility Slip system determination grain boundary cohesion 

摘      要：It is know from literature that small additions(1 wt%)of Ca,Al and Zn significantly improve the intrinsic ductility of *** exact role of each element,both qualitatively and quantitatively,and their combined effects,however,are poorly *** we achieved a much clearer view on the quantitative role of each element with respect to ductility improvement and on the collaborative effect,particularly of Ca and Zn in *** of our findings and conclusions are in disagreement with data and interpretation found in *** different alloys,namely,Mg-0.1 Ca,Mg-0.1 Ca-1 Al,Mg-0.05 Ca-1 Al,Mg-0.1 Ca-2 Al-1 Zn(all are in wt%)were selected for this *** alloys were treated such that *** grain sizes and textures were *** largely excludes the effect of extrinsic factors on ***-guided slip trace analyses reveal that the addition of Ca eases activation of prismatic and pyramidal II slip *** in-situ deformation experiments in SEM and atom probe tomography observations of grain boundaries direct evidence is given for the individual and synergetic effects of Ca and Zn on grain boundary cohesion as an important contribution to improve the ductility of these *** conclude that Ca reduces the slip anisotropy and ameliorates ductility,however,the weak grain boundary cohesion in the Mg-0.1 wt%Ca alloy limits the material’s tensile *** addition of Zn alters the Ca segregation at the grain boundaries and helps to retain their cohesive strength,an effect which thus enables higher ductility and *** further addition of Al primarily improves the *** results show that the balanced influence of reduced slip anisotropy on the one hand and increased grain boundary cohesion on the other hand allow to design a high strength high ductility rare-earth free Mg alloy.