定向凝固速度对Mg-3Zn-Mn导热性能的影响  

Effect of the Directional Solidified Velocities on Thermal Conductivity of Mg-3Ag-Zn Alloys

作　　者：马雁翔[1] 李秋书[1] 王金红 韩泽坤 MA Yanxiang1, LI Qiushu1, WANG Jinhong2 , HAN Zekun2(1. Academy of Materials Science and Engineering, Taiyuan University of Science and Technology, Taiyuan 030024, China; 2. Zhiqi Railway Equipment Co., Ltd., Taiyuan 030032, Chin)

机构地区：[1]太原科技大学材料科学与工程学院,山西太原030024 [2]智奇铁路设备有限公司研发中心,山西太原030032

出　　处：《铸造技术》2018年第3期558-561,共4页Foundry Technology

摘　　要：通过制备铸态和不同定向凝固速度(V=15、25、50、75μm/s)的Mg-3Zn-Mn合金,比较铸态与定向凝固合金导热性能,并研究定向凝固速度对导热性能的影响及变化规律。结果表明,晶界作为一种面缺陷,是声子和光子的散射源,散射源越多,合金的导热性能越差。因此,铸态Mg-3Zn-Mn导热性能低于定向凝固合金。对于定向凝固合金,随着定向凝固速度的增加,合金导热性能降低。定向凝固速度V=15μm/s时,合金导热性能最好。As-cast and directional solidified Mg-3Zn-Mn alloy at four different pulling velocities （V=15 μm/s, V=25 μm/s, V=50 μm/s, V=75 μm/s ） were prepared, and the influence of directional solidification process on the thermal conductivity, and it changing regularity were investigated. The results show that grain boundaries are as a kind of face defects, and are the scattering source of phonons and photons. As a result, the thermal conductivity of the alloy is lower with increase the grain boundaries. The thermal conductivity of as-cast Mg-3Zn-Mn alloy is lower than directional solidified Mg-3Zn-Mn alloy. In addition, the thermal conductivity of directional solidified alloy decreases with the increase of directional solidified velocity, and the best thermal conductivity of alloy is the pulling velocities V is 15μm/s.

关 键 词：MG合金 定向凝固 晶界 导热性能 

分 类 号：TG244[金属学及工艺—铸造]