Influence of Extrusion Temperature on Microstructure and Mechanical Properties of Mg-3Zn-2.5Al-2.5Ca Alloy

CHEN Ding, ZHANG Kai, DONG Peng, CHEN Zhenhua

Abstract

The effect of extrusion temperatures on the microstructures and mechanical properties of Mg-3Zn-2.5Al-2.5Ca (ZAC333) alloy was investigated by metallograph, SEM, XRD and tensile tests. The results show that the average grain size of the as-cast alloy is 185 μm. Due to the dynamic recrystallization, the grain size of as-extruded alloys was reduced from 6.32 μm to 3.36 μm with the extrusion temperature decreasing from 623 K to 523 K. The second phase of semi-continuous Al2Ca and continuous Ca2Mg6Zn3 was broken, which distributed along the grain boundary in the as-cast ZAC333 alloy. Compared with as-cast alloy, the mechanical properties of as-extruded ZAC333 alloy were improved. The tensile and yield strength of as-extruded alloy increased from 176 to 292 MPa, 264 to 334 MPa, respectively, while elongation decreased from 20% to 9%. The improvement of mechanical properties for ZAC333 alloy can be attributed to the couple effects of refined crystalline strengthening caused by dynamic recrystallization and dispersion strengthening for the refined second phases during hot extrusion.

 

 

Keywords: ZAC333 alloy,  extrusion temperature,  dynamic recrystallization,  the second phase,  mechanical properties


Full Text:

PDF


References


ZHANG Xinming.XIAO Yang.CHEN Jianmei, et al. Influence of extrusion temperature on microstructures and mechanical properties of Mg-9Gd-4Y-0.6Zr allopy [J]. The Chinese Journal of Nonferrous Metals.2006.16(3): 518—523. (In Chinese)

CHEN Jihua.CHEN Guanqing.YAN Hongge et al. Effects of rolling mode on bio-corrosion behavior of magnesium alloys [J]. Joural of Hunan University: Natural Sciences, 2016. 43 (12) :24-30.(In Chinese)

LI Chengjie. SUN Hongfei.FANG Wenbin. Effect of extrusion temperature on microstructures and mechanical properties of Mg-3Zn-0.2Ca-0.5Y alloy[J]. Procedia Engineering. 2014.81: 610-615.

PARK SS.YOU В S. YOON D J. Effect of the extrusion conditions on the texture and mechanical properties of indirect-extruded Mg-3Al-lZn alloy[J]. Journal of Materials Processing Technology.2009.209(18): 5940-5943.

SUN Hongfei. LI Chengjie. FANG Wenbin. Evolution of microstructure and mechanicail properties of Mg-3Zn0.2Ca-0.5Y alloy by extrusion at various temperatures [J], Journal of Materials Processing Technology. 2016.229: 5940—5943.

MO Wenfei, ZHANG Liang, WU Guohua., et al. Effects of processing parameters on microstructure and mechanical properties of squeeze-cast Mg-12Zn-4AI-0.5 Ca aIloy [J]. Materials Design.2014.63. 729-737.

SURESH K.RAO К P.PRASAD Y.et al.Study of hotfoiing behavior of as-cast Mg-3AI-lZn-2Ca alloy towards optimization of its liot workability [J]. Materials &- Design.2014.57. 697 -704.

YU B.LI Y.SONG H. et al. Mechanical properties of mg-8zn-4al-xca extruded magnesium alloy tube at elevated temperature [J].Materials Science Forum.2007.546: 305 — 310.

JIANG Zhongtao. JIANG Bin. YANG Hong.et al. Influence of the Al2Ca phase on microstructure and mechanical properties of Mg-AI-Ca alloys [J]. Journal of Alloys and Compounds. 2015.647; 357-363.

YU H.PARK S H. YOU В Si Development of extraordinary high strength Mg 8Л1-0.5 Zn alloy via a low temperature and slow speed exirusion[J]. Materials Science and Engineering: A.2014.610: 445-449.


Refbacks

  • There are currently no refbacks.