添加TiSiC含量对放电等离子烧结制备的BC-TiB复合陶瓷力学性能的影响

Effect of Additive TiSiC Content on the Mechanical Properties of BC-TiB Composites Ceramics Sintered by Spark Plasma Sintering.

作者信息

Yan Xingheng, Zhou Xingui, Wang Honglei

机构信息

Science and Technology on Advanced Ceramic Fibers and Composites Laboratory, College of Aerospace Science and Engineering, National University of Defense Technology, Changsha 410073, China.

出版信息

Materials (Basel). 2020 Oct 16;13(20):4616. doi: 10.3390/ma13204616.

DOI:10.3390/ma13204616

PMID:33081251

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7602970/

Abstract

BC-TiB composite ceramics with ultra-high fracture toughness were successfully prepared via spark plasma sintering (SPS) at 1900 °C using BC and TiSiC as raw materials. The results showed that compared with pure BC ceramics sintered by SPS, the hardness of BC-TiB composite ceramics was decreased, but the flexural strength and fracture toughness were significantly improved; the fracture toughness especially was greatly improved. When the content of TiSiC was 30 vol.%, the BC-TiB composite ceramic had the best comprehensive mechanical properties: hardness, bending strength and fracture toughness were 27.28 GPa, 405.11 MPa and 18.94 MPa·m, respectively. The fracture mode of the BC-TiB composite ceramics was a mixture of transgranular fracture and intergranular fracture. Two main reasons for the ultra-high fracture toughness were the existence of lamellar graphite at the grain boundary, and the formation of a three-dimensional interpenetrating network covering the whole composite.

摘要

以BC和TiSiC为原料，通过在1900℃下进行放电等离子烧结（SPS）成功制备了具有超高断裂韧性的BC-TiB复合陶瓷。结果表明，与通过SPS烧结的纯BC陶瓷相比，BC-TiB复合陶瓷的硬度降低，但抗弯强度和断裂韧性显著提高；尤其是断裂韧性得到了极大提高。当TiSiC含量为30 vol.%时，BC-TiB复合陶瓷具有最佳的综合力学性能：硬度、抗弯强度和断裂韧性分别为27.28 GPa、405.11 MPa和18.94 MPa·m。BC-TiB复合陶瓷的断裂模式为穿晶断裂和沿晶断裂的混合。断裂韧性超高的两个主要原因是晶界处存在层状石墨，以及形成了覆盖整个复合材料的三维互穿网络。