摘要
以Y_(2)O_(3)为烧结助剂,采用放电等离子烧结技术制备了以MoSi_(2)为第二相的α-Sialon陶瓷,研究了MoSi_(2)添加量(0~10%,质量分数)对陶瓷微观结构和性能的影响。结果表明:添加MoSi_(2)后,陶瓷中α-Sialon晶粒从等轴状变为长棒状,且随着MoSi_(2)添加量的增多,长棒状α-Sialon晶粒显著增多,长径比增大,当MoSi_(2)质量分数为10%时,晶粒尺寸呈现显著的双峰分布;当MoSi_(2)质量分数从0增加到10%时,陶瓷的相对密度由99.0%增加到99.7%,硬度由21.12 GPa降低到20.44 GPa,断裂韧度由4.80 MPa·m^(1/2)增加到6.13 MPa·m^(1/2);在干切削镍基高温合金时,添加质量分数10%MoSi_(2)的陶瓷刀具在达到磨损标准时的切削长度是未添加MoSi_(2)陶瓷刀具的1.5倍,可见该刀具切削性能优异,其主要磨损形式为后刀面磨损和沟槽磨损,主要磨损机理为黏着磨损和磨粒磨损。
Using Y_(2)O_(3) as sintering aid,α-Sialon ceramics with MoSi_(2) as a second phase were prepared by spark plasma sintering.The effect of the MoSi_(2) adding amount(0-10 wt%)on the microstructure and properties of the ceramics was studied.The results show that after adding MoSi_(2),theα-Sialon grains in the ceramics changed from equiaxed to long rod-like.With increasing MoSi_(2) adding amount,the long rod-likeα-Sialon grains increased significantly,and the aspect ratio increased;when the addition of MoSi_(2) was 10 wt%,the grain size exhibited a significant bimodal distribution.When the addition of MoSi_(2) increased from 0 to 10 wt%,the relative density of the ceramics increased from 99.0%to 99.7%,the hardness decreased from 21.12 GPa to 20.44 GPa,and the fracture toughness increased from 4.80 MPa·m^(1/2) to 6.13 MPa·m^(1/2).In dry cutting of nickel-based superalloy,the cutting length of the ceramic tool with 10 wt%MoSi_(2) was 1.5 times that of the ceramic tool without MoSi_(2) when it reached the wear standard,indicating the tool had excellent cutting performance;the main wear forms of the tool were flank wear and groove wear,and the main wear mechanisms were adhesive wear and abrasive wear.
作者
张展
谭大旺
罗嗣春
郭伟明
林华泰
ZHANG Zhan;TAN Dawang;LUO Sichun;GUO Weiming;LIN Huatai(School of Electromechanical Engineering,Guangdong University of Technology,Guangzhou 510006,China)
出处
《机械工程材料》
CAS
CSCD
北大核心
2022年第5期47-52,57,共7页
Materials For Mechanical Engineering
基金
广东省引进创新科研团队计划资助项目(2013G061)。
