摘要
以新型耐火材料AlN为基体,添加不同含量的高活性h-BN及烧结助剂Y_(2)O_(3),在1850℃保温4 h下无压烧结制备出无氧、易加工的AlN/BN耐火复合陶瓷,分析了该复合陶瓷的显微组织,研究了其与TiAl熔体的界面润湿规律及界面反应。结果表明,BN颗粒的加入可以有效填充AlN颗粒间隙,促进复合陶瓷的烧结致密化,当添加质量分数5%BN颗粒时,复合陶瓷致密度达到最高,为89.24%。复合陶瓷的组织由AlN、BN及钇铝酸盐Y_(4)Al_(2)O_(9)组成,其中Y_(4)Al_(2)O_(9)主要分布在AlN颗粒界面处。BN颗粒可以降低复合陶瓷与TiAl熔体的界面润湿性,其中含5%BN的复合陶瓷与TiAl熔体的界面润湿角约为136°,表明二者润湿较差,复合陶瓷表现出良好的化学惰性。界面反应实验发现复合陶瓷具有良好的抗TiAl熔体侵蚀性能,其与TiAl熔体的界面平整清晰,界面层厚度为9.5μm,未发生明显元素扩散,表明了AlN/BN复合陶瓷是一种极具潜力的钛合金熔炼用耐火材料。
AlN/BN refractory composite ceramics,which is oxygen-free and easy to process,were prepared by pressure-free sintering at 1850°C for 4 h with a new type of refractory material AlN as the matrix,adding different contents of high-activity h-BN and sintering assistant Y_(2)O_(3).The microstructure of the composite ceramics was analyzed,and the wetting behavior and interfacial reaction between the composite ceramic and TiAl melt were studied.The results show that the addition of BN particles can effectively fill the gap of AlN particles and promote the sintering densification of composite ceramics.When adding 5wt%BN particles,the density of the composite ceramics reaches the highest of 89.24%.The microstructure of the composite ceramics is composed of AlN,BN and yttrium aluminate Y_(4)Al_(2)O_(9)that is mainly distributed at the interface of AlN particles.The interfacial wettability between the composite ceramics and the TiAl melt is reduced by addition of BN particles.The interfacial wettability angle of the composite ceramic containing 5wt%BN and the TiAl melt is about 136°,indicating that the composite ceramics and TiAl melt are poorly wetted and the composite ceramics exhibit good chemical inertia.The interfacial reaction experiments show that the composite ceramics have good corrosion resistance to TiAl melt.The interface between the composite ceramics and TiAl melt is smooth and clear,the thickness of the interfacial layer is only 9.5μm,and no obvious element diffusion occurs.It indicates that AlN/BN composite ceramics are a potential refractory for titanium alloy melting.
作者
张生庭
张卫文
李宁
赵超
王智
Zhang Shengting;Zhang Weiwen;Li Ning;Zhao Chao;Wang Zhi(School of Mechanical and Automotive Engineering,South China University of Technology,Guangzhou 510641,China;School of Materials Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,China)
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2023年第8期2919-2925,共7页
Rare Metal Materials and Engineering
基金
国家重点研发计划(2020YFB2008300,2020YFB2008301,2020YFB2008305)
广东省自然科学基金(2020A1515011242)
广东省国际科技合作领域粤港澳大湾区国际科技创新中心建设基金(2021A0505050002)
高端外国专家引进计划(G2021163004L)。
关键词
氮化铝
六方氮化硼
耐火复合陶瓷
界面润湿角
界面反应
aluminum nitride
h-Boron nitride
refractory composite ceramics
interface wetting angle
interface reaction
