Preparation of dense B4C ceramics by spark plasma sintering of high-purity nanoparticles
Preparation of dense B4C ceramics by spark plasma sintering of high-purity nanoparticles
复制标题
高纯纳米颗粒放电等离子体烧结制备致密B4C陶瓷
DOI：
10.1016/j.jeurceramsoc.2021.02.036
复制
发表时间：
2021-03-24
影响因子：
5.7
通讯作者：
Tian, Yongjun
中科院分区：
文献类型：
--
作者：
Li, Penghui;Ma, Mengdong;Tian, Yongjun
碳化硼（B4 C）是一种重要的结构陶瓷材料，但烧结性差、断裂韧性低，限制了其应用。纳米粉体具有粒径小、化学活性高、烧结性能好等特点，有利于制备致密的B_4C陶瓷。采用放电等离子烧结法（SPS）制备了密度接近理论值的单相B4 C陶瓷。结果表明，最佳SPS条件为1850 ℃保温;在此条件下，样品表现出增强的机械性能，包括维氏硬度为33.9 GPa，断裂韧性为3.81 MPa m1/2和弯曲强度为554.7 MPa。透射电子显微镜（TEM）分析表明，晶界处存在非共格孪晶，而不是非晶相或第二相，进一步证实了所得B4 C陶瓷的高纯度和高致密化。
Boron carbide (B4C) is an important structural ceramic material, however, the use of this material is limited by its poor sinterability and low fracture toughness. Nano-sized powders have small particle size, high chemical activity and great sintering ability, which can promote the fabrication of the dense B4C ceramics. Herein, by spark plasma sintering (SPS) homemade high-purity nanopowders, single phase B4C ceramics with density close to the theoretical value were prepared. Results showed that the best SPS condition was holding at temperature of 1850 ?C for 4 min. Under this condition the sample exhibited enhanced mechanical properties including Vickers hardness of 33.9 GPa, fracture toughness of 3.81 MPa m1/2 and flexure strength of 554.7 MPa. Transmission electron microscopy (TEM) analysis shows that non-coherent twins exist at the grain boundary instead of amorphous phase or second phase, which further confirms the high purity and high densification of the obtained B4C ceramics.