复合添加MgO和La2O3对纳米微晶氧化铝陶瓷微观结构的影响
Effects of MgO and La2O3 Composite Additives on Microstructure of Nano-Microcrystalline Alumina Ceramics
李慧 1张金平 1高景霞 1王二萍 1张洋洋1
作者信息
- 1. 黄河科技学院工学部,郑州 450006
- 折叠
摘要
纳米微晶氧化铝磨料具有良好的通用性和高精度磨削能力,且性价比较高,在机械制造、轴承、模具、汽车等领域有广泛的应用潜力.本研究以勃姆石(γ-AlOOH)为原料,MgO、La2O3为添加剂,采用溶胶-凝胶工艺合成纳米微晶氧化铝.通过差示扫描量热仪、X射线衍射仪、扫描电子显微镜和从头算分子动力学方法模拟计算研究了添加剂对微晶氧化铝相转化、物相组成、微观结构及力学性能的影响.结果表明:复合添加MgO和La2O3可以使氧化铝中间相θ-Al2O3向α-Al2O3转化的温度从1 257℃降低到1 105 ℃,将致密化温度从1 600 ℃降低到1 350 ℃,将微晶氧化铝的晶粒尺寸从1.04 mm减小到120 nm,实现了低温致密烧结.
Abstract
The nanocrystalline alumina abrasive,with its excellent versatility and high-precision grinding capability,has become a cost-effective choice for various applications in fields such as mechanical manufacturing,bearings,molds and automobiles.In this study,nano microcrystalline alumina was synthesized by sol-gel process,with boehmite(γ-AlOOH)as raw material,MgO and La2O3 as additives.The effects of MgO and La2O3 additives on the phase transformation,phase composition,microstructure and mechanical properties of nanocrystalline alumina were investigated by differential scanning calorimetry,X-ray diffraction,scanning electron microscopy and ab initio molecular dynamics simulation.The results show that MgO and La2O3 composite additives can reduce the transformation temperature of alumina from the intermediate phaseθ-Al2O3 to α-Al2O3 from 1 257℃to 1 105 ℃,lower the densification temperature of the material from 1 600℃to 1 350℃,and reduce the grain size of nanocrystalline alumina from 1.04 mm to 120 nm,thus realizing the low-temperature dense sintering.
关键词
纳米微晶/Al2O3/MgO/La2O3/溶胶-凝胶/添加剂/低温烧结Key words
nano-microcrystalline/Al2O3/MgO/La2O3/sol-gel/additive/low-temperature sintering引用本文复制引用
基金项目
河南省科技攻关项目(212102210187)
河南省科技攻关项目(212102210603)
河南省科技攻关项目(232102210183)
出版年
2024
国家科技期刊平台
NSTL
万方数据