李鑫,谢辉,张亚龙,魏鑫.高温度梯度定向凝固单相Mg2Sn合金的制备及其热电性能[J].稀有金属材料与工程,2020,49(7):2436~2443.[Li Xin,Xie Hui,Zhang Yalong,Wei Xin.Preparation and Thermoelectric Properties of Single-phase Mg2Sn Alloys by High Temperature-gradient Directional Solidification[J].Rare Metal Materials and Engineering,2020,49(7):2436~2443.]
高温度梯度定向凝固单相Mg2Sn合金的制备及其热电性能
投稿时间:2019-12-08  修订日期:2019-12-20
中文关键词:  晶体生长  高温度梯度定向凝固  热电性能  Mg[sub_s]2[sub_e]Sn
基金项目:国家自然科学基金青年项目(项目号:51904219); 西安航空学院校级科研资(项目号:2019KY0203)
中文摘要:
      高温度梯度(180K/cm)定向凝固方法可制备单相Mg2Sn晶体,通过凝固理论对平-胞转换临界速率进行了计算,并预测了单相Mg2Sn晶体的生长距离,与试验结果相吻合。此方法获得的Mg2Sn晶体由于去除了第二相Sn的影响,可以获得更好的热电性能,在测试温度区间(300-700K)内,未掺杂条件下最大Seebeck系数和电导率值分别可达-261μVK-1和525?-1m-1,通过Bi掺杂来对电导率进行优化后,功率因子最高可达2.29mWm-1K-2。单相Mg2Sn晶体的热导率也得到大幅降低,500K时,最小值为4.3Wm-1K-1,Bi掺杂量为1.5at.%时,热电优值最高可达到0.21。这一方法可以为制备高性能的Mg2BIV体系三元固溶体合金提供参考。
Preparation and Thermoelectric Properties of Single-phase Mg2Sn Alloys by High Temperature-gradient Directional Solidification
英文关键词:crystal growth  high temperature-gradient directional solidification  thermoelectric properties  Mg2Sn
英文摘要:
      Single-phase Mg2Sn crystal was successfully directionally solidified from the melt with a high temperature gradient of 180K/cm. The critical velocity of planar interface and solidified distance for the growth of single-phase Mg2Sn crystal is predicted theoretically and agrees well with the experimental result. The grown Mg2Sn crystals exhibit better thermoelectric performance without influence of the second phase Sn. At the temperature ranging from 300 to 700K, the maximum Seebeck coefficient S and electrical conductivity σ reached -261μVK-1 and 525?-1m-1, respectively. The top value of power factor is 2.29mWm-1K-2 after the doped Bi optimization. The minimum thermal conductivity κ was measured as 4.3Wm-1K-1 at T=500K. The maximum figure of merit is 0.21 at the doping concentration of 1.5at.%Bi. The method developed in this paper can provide a methodological reference for the preparation of ternary Mg2BIV solid solution.
作者单位E-mail
李鑫 西安航空学院 lixin005@xaau.edu.cn 
谢辉 西安航空学院  
张亚龙 西安航空学院  
魏鑫 西安航空学院  
摘要点击次数: 33
全文下载次数: 21
查看全文  查看/发表评论  
关闭