标题:
Sr对Mg-6Zn-2Al-2Ca合金显微组织的影响The Effect of Sr Addition on the Microstructure of Mg-6Zn-2Al-2Ca Magnesium Alloy
作者:
邱克强, 张伟刚, 任英磊, 尤俊华
关键字:
Mg-6Zn-2Al-2Ca合金金, Sr元素, 组织演化Mg-6Zn-2Al-2Ca Alloy; Sr Addition; Microstructure Evolution
期刊名称:
《Material Sciences》, Vol.2 No.1, 2012-01-19
摘要:
采用扫描电镜、X射线衍射仪和光学显微镜研究了Mg-6Zn-2Al-2Ca-xSr (x = 0, 0.5, 1, 2, 3)合金随Sr的含量变化组织形貌的演化规律。实验结果表明：0.5%Sr可以抑制β-Mg17Al12相的形成；Sr的加入，具有增加Mg-6Zn-2Al-2Ca液态金属成分过冷的能力，使胞状组织向树枝状组织发展，枝晶组织随Sr含量的增加而得到细化。当Sr含量达到3%时，形成非枝晶状组织。当Sr含量超过2%时，组织中板块状Mg17Sr2相尺寸明显增大，对组织的演化规律进行了讨论。
The effect of Sr addition on microstructure evolution of Mg-6Zn-2Al-2Ca-xSr (x = 0.5, 1, 2, 3) alloys was investigated by using scanning electron microscope (SEM), X-ray diffraction (XRD) and optical microscope. The results show that the 0.5% Sr addition can restrain the formation of β-Mg17Al12 phase. The constitutional undercooling increases with Sr addition, which changes the structure from cellular to dendritic. The dendritic structure becomes more refinement with Sr addition. Furthermore non-dendritic structure is formed when Sr content is 3%. However, a paddle Mg17Sr2 structure was observed when Sr content is 2% and its size increases with Sr. The structure evolution of Mg-6Zn-2Al-2Ca alloy with Sr addition was discussed.