原位析出TiB2-Ti2AlN增强TiAl合金力学性能
Enhancement in Mechanical Properties of TiAl Alloys by In-Situ Precipitation of Hybrid TiB2-Ti2AlN
王玉鹏 1李思颖 1马腾飞 1王晓红 1董多 2朱冬冬2
作者信息
- 1. 衢州学院浙江省空气动力装备技术重点实验室,浙江衢州 324000
- 2. 衢州学院浙江省空气动力装备技术重点实验室,浙江衢州 324000;台州学院材料科学与工程学院,浙江台州 318000
- 折叠
摘要
采用放电等离子烧结技术对TiAl合金和BN纳米片混合粉末在1300 ℃下进行烧结,原位合成了 TiB2-Ti2AlN/TiAl复合材料,并对TiAl复合材料的显微组织演变和室温力学性能进行了研究.结果表明,添加低含量BN纳米片的TiAl复合材料为全片层组织,而添加高含量BN纳米片的TiAl复合材料向近片层组织转变.此外,原位合成的TiB2-Ti2AlN颗粒均匀分布在片层团晶界处,显著细化了复合材料组织.当添加质量分数为0.5％的BN纳米片时,TiB2-Ti2AlN颗粒在片层团晶界处形成连续核壳结构.室温压缩和摩擦磨损结果表明,随着BN纳米片质量分数从0％增加到1％,TiAl复合材料的显微硬度和抗压缩强度显著提高,摩擦磨损系数从0.59降低到0.47,磨损率降低了29.9％.TiAl复合材料优异的力学性能主要归因于原位析出的TiB2-Ti2AlN颗粒、细化的显微组织和核壳结构所产生的强化效应.
Abstract
TiAl alloy was mixed with BN nanoplates and then sintered at 1300 ℃ through spark plasma sintering technique,and the hybrid TiB2-Ti2AlN/TiAl composites were in-situ prepared.The microstructural evolution and mechanical properties at room temperature of TiAl composites were investigated.Results show that a fully lamellar microstructure can be achieved in the TiAl composites with BN nanoplates of lower content,whereas a transformation to the nearly lamellar microstructure can be observed under higher BN nanoplate content conditions.The microstructure of TiAl composites is significantly refined due to the even distribution of in-situ prepared TiB2-Ti2AlN particles at the lamellar colony boundaries.Notably,a continuous core-shell structure of TiB2-Ti2AlN particles is formed at the lamellar grain boundary after adding 0.5wt％BN nanoplates.The results of compression and friction wear at room temperature show that the hardness and compressive strength of TiAl composites are greatly improved with the increase in BN nanoplate content from 0wt％to 1wt％.Meanwhile,the average coefficient of friction decreases from 0.59 to 0.47,and the wear rate decreases by 29.9％.These remarkable mechanical properties are mainly attributed to the strengthening effects of the in-situ formation of TiB2-Ti2AlN particles,refined microstructure,and core-shell structure.
关键词
TiAl复合材料/TiB2-Ti2AlN颗粒/放电等离子烧结/力学性能Key words
TiAl composite/TiB2-Ti2AlN particle/SPS/mechanical properties引用本文复制引用
出版年
2024
NETL
NSTL
万方数据