金刚石/纳米氧化铝陶瓷复合材料高温高压合成物相结构分析
Phase Structure Analysis of Diamond/Nano-alumina Ceramic Composite Synthesized at High Temperature and High Pressure
朱新雨 1郭宇 1庞诚宇 2董俊言 1付玉博 1姜丽娜 1董书山1
作者信息
- 1. 吉林大学超硬材料国家重点实验室,吉林长春 130012
- 2. 河南厚德钻石科技有限公司,河南商丘 476200
- 折叠
摘要
以正硅酸乙酯(TEOS)为反应前驱体,采用溶胶-凝胶法在金刚石微粉(粒度0.1～4 μm)表面包覆一层非晶纳米氧化硅膜层,同时在覆膜层中加入纳米Si粉和纳米Al2O3粉,制备出金刚石/纳米SiO2/纳米Al2O3复合包覆体.采用高温高压(HTHP)技术,将复合包覆材料置于六面顶压机中,以压力5 GPa、温度1 100 ℃～1 700 ℃、保温20 min的条件制备了金刚石-氧化铝陶瓷烧结体.在高温高压合成过程中,纳米SiO2从非晶态转变为晶态,原料纳米Al2O3中的γ-相、θ-相转变为稳定的α-相,同时,SiO2和Al2O3之间形成了 Al2SiO5(莫来石)相,由此,通过高温高压下反应原料的结构转变与复合,可以获得致密度良好的金刚石-氧化铝复合材料.
Abstract
Tetraethyl orthosilicate(TEOS)was used as a precursor to coat an amorphous nano-SiO2 film on the surface of the fine-grained diamond powders(0.1-4μm)by sol-gel method,meanwhile,some nanoparticales of silicon and alumina were also added to the coated film to form diamond composite particles.Using high temperature and high pres-sure(HTHP)technique,The sintered body was obtained by placing the as-prepared dia-mond composite in a cubic press under conditions of pressure 5 GPa,holding for 20 mi-nutes at different temperatures ranging from 1 100 ℃ to 1 700 ℃.During the HTHP process,nano-SiO2 phase in the coated film transforms from an amorphous state to a crystalline state,and the raw powders of nano-Al2 O3 transformes from γ-phase and θ-phase to the stable α-phase,furthermore,an Al2SiO5(mullite)phase was formed between SiO2 and Al2O3.Finally,through the structural transformation and combination of reac-tion materials under HTHP conditions,a kind of diamond-alumina composite with good density can be obtained.
关键词
金刚石/纳米氧化铝/高温高压合成/复合材料/物相结构分析Key words
Diamond/Nano-alumina/High temperature and high pressure synthesis/Composite materials/Phase structure analysis引用本文复制引用
出版年
2024
NETL
NSTL
万方数据