标题：Degradation of strength properties and its fracture behaviour of TiB2-TiC-based composite ceramic cutting tool materials at the high temperature
作者：Zou, Bin; Ji, Wenbin; Huang, Chuanzhen; Xu, Kaitao; Li, Shasha
作者机构：[Zou, Bin; Ji, Wenbin; Huang, Chuanzhen; Xu, Kaitao] Shandong Univ, Sch Mech Engn, Ctr Adv Jet Engn Technol CaJET, Jinan 250061, Peoples R China.; [ 更多
通讯作者地址：[Zou, B]Shandong Univ, 17923 Jing Shi Rd, Jinan 250061, Peoples R China.
来源：INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
关键词：Microstructure; Strength; Degradation; Cutting tools; High temperature
摘要：Strength retention is important for tool materials at high temperature because cutting temperature in machining is ranged from room temperature to 1000 degrees C. A study examining the strength properties and fracture behaviour of TiB2-TiC-based composite ceramic cutting tool materials is presented at different temperatures. MoSi2 and SiC additives are considered to investigate their effects on the density, microstructure, strength and failure mechanism of composites. It is found that the addition of SiC contributed more to the high-temperature strength of composites than MoSi2, but it did not improve the room-temperature strength, despite grain refinement. The TBAVS8 composite has a flexural strength of 800 MPa at room temperature and can retain 75% at 900 degrees C. At room temperature, the fracture behaviour of composites was dominated by the strong bonding of the Ni binder phase. At high temperatures, the softer Ni binder phase was pinned, and its sliding was inhibited by SiC particles, which decelerated the strength degradation. (C) 2014 Elsevier Ltd. All rights reserved.