(1. 东北大学 材料与冶金学院，沈阳 110004；
2. 东北大学 辽宁省高校硼资源生态化综合利用技术与硼材料重点试验室，沈阳 110004；
3. 东北大学 辽宁省硼资源综合开发利用工程技术研究中心，沈阳 110004)
摘 要: 以B粉、Al粉和B4C粉为原料，采用粉末冶金法在1 200 ℃、高纯氩气保护条件下，烧结制备了B4C-AlB12-Al复合材料。利用XRD和SEM对其相组成和显微结构进行了表征，研究了初始原料中Al含量对材料中AlB12的晶形转变、力学性能和常温导电性能的影响。结果表明：烧结产物由B4C、AlB12、Al及Al3BC和少量Al2O3组成，随Al含量的增加，材料中AlB12的存在形式由α相向β相转变；Al含量大于31.99%时，AlB12完全为β-AlB12相；当原料中Al含量为39.71%时，试样的硬度最高为661 MPa；当Al含量为45.85%时，试样的抗弯强度最高达64 MPa；当Al含量为45.85%左右时，Al的加入量是决定材料能否形成导电网络的最低加入量，此时材料的电阻率为9.82×10−2 Ω·cm。
关键字: B4C；AlB12；力学性能；导电性能
（1. School of Materials and Metallurgy, Northeastern University, Shenyang 110004, China;
2. Liaoning Key Laboratory for Ecologically Comprehensive Utilization of Boron, Northeastern University,
Shenyang 110004, China;
3. Resources and Materials, Engineering and Technology Research Center for Boron Resource Comprehensive Development and Application of Liaoning Province, Northeastern University, Shenyang 110004, China）
Abstract:B4C-AlB12-Al composites were sintered by powder metallurgy method under high pure argon shield at 1 200 ℃ using boron powder, aluminium powder and boron carbide powder as raw materials. The phase composition and microstructures were characterized using XRD and SEM. The effect of Al content in materials on crystal transfer, mechanical properties and room-temperature electrical conductivity were studied. The results show that the main phase of the reduction product are B4C, AlB12, Al, Al3BC and small amount of Al2O3. With the increase of Al content, α-AlB12 is converted into β-AlB12. When the Al content reach 39.71% and 45.85%, the maximum hardness and bending strength are 661 MPa and 64 MPa, respectively. Al content is about 45.85%, which is the minimum adding amount can determine if the prepared materials can form the conductive network. The minimum adding amount of Al content is 45.85%, and the resistance rate is 9.82×10−2 Ω·cm
Key words: B4C; AlB12; mechanical properties; electrical conductivity
