金属热处理 ›› 2023, Vol. 48 ›› Issue (6): 142-146.DOI: 10.13251/j.issn.0254-6051.2023.06.026

• 组织与性能 • 上一篇    下一篇

TiAlNb9合金表面B-Y改性硅化物渗层的组织及热冲击性能

王存喜1, 梁国栋1, 田兴达1, 李涌泉2   

  1. 1.北方民族大学 材料科学与工程学院, 宁夏 银川 750021;
    2.北方民族大学 机电工程学院, 宁夏 银川 750021
  • 收稿日期:2022-12-18 修回日期:2023-04-03 发布日期:2023-08-11
  • 通讯作者: 李涌泉,副教授,博士,E-mail:8386595@163.com
  • 作者简介:王存喜(1997—),男,硕士研究生,主要研究方向为钛铝合金的表面改性处理,E-mail:1253484047@qq.com。
  • 基金资助:
    国家自然科学基金(51961003, 52161009);宁夏自然科学基金(2022AAC03224);服务宁夏九大产业专项(FWNX42)

Microstructure and thermal impact property of B-Y doped silicon compound coating on TiAlNb9 alloy surface

Wang Cunxi1, Liang Guodong1, Tian Xingda1, Li Yongquan2   

  1. 1. School of Materials Science and Engineering, North Minzu University, Yinchuan Ningxia 750021, China;
    2. School of Electrical and Mechanical Engineering, North Minzu University, Yinchuan Ningxia 750021, China
  • Received:2022-12-18 Revised:2023-04-03 Published:2023-08-11

摘要: 采用15Si-4B-8NaF-2Y2O3-71Al2O3(质量分数, %)渗剂包埋渗法在TiAlNb9合金表面制备了B-Y改性的硅化物渗层, 并通过扫描电镜、X射线衍射仪及电子探针分析了渗层的结构及相组成, 对比研究了Si-B-Y共渗层制备前后TiAlNb9合金热冲击性能的变化。结果表明, 经1050 ℃保温6 h所制备的Si-B-Y共渗层具有组织均匀致密的复合结构, 厚约14 μm, 其外层主要为TiB2相和(Ti, Nb)Si2相, 中间层为(Ti, Nb)5Si3相, 内层为TiAl2相和少量TiB相。在1000 ℃热冲击下, TiAlNb9基体裂纹一旦产生, 将会持续扩展, 中间会有树枝状裂纹产生, 在热冲击47次后出现贯穿性裂纹;而Si-B-Y共渗层裂纹萌生时间较长, 裂纹的萌生具有多发和弥散性, 随着热冲击次数的增加, 最终多处细小裂纹汇合一处, 在热冲击59次后贯穿基体, 但裂纹未在膜基界面处发生横向扩展, 且整体渗层未出现脱落的现象, 表明Si-B-Y共渗层可以在一定程度上提高TiAlNb9合金的抗热冲击性能。

关键词: TiAlNb9合金, 包埋渗法, 硅-硼-钇共渗层, 热冲击性能

Abstract: B-Y doped silicon compound coating was prepared on surface of TiAlNb9 alloy by pack cementation process with 15Si-4B-8NaF-2Y2O3-71Al2O3(mass fraction, %), the structure and phase composition of the co-deposition coating were analyzed by means of scanning electron microscopy, X-ray diffractometry and electron probe, and the thermal impact properties of Si-B-Y co-deposition coating and TiAlNb9 substrate were compared. The results show that the Si-B-Y co-deposition coating prepared by holding at 1050 ℃ for 6 h has an uniform and dense composite structure with a thickness of about 14 μm. The outer layer consists of TiB2 and (Ti, Nb)Si2 phases, the middle layer consists of (Ti, Nb)5Si3 phase, and the inner layer consists of TiAl2 and small amounts of TiB phases. Under the thermal impact at 1000 ℃, the substrate cracks in the TiAlNb9 alloy continue to grow, and there are bifurcated cracks in the middle, the penetrating cracks appear after 47 times of thermal impact. However, the Si-B-Y co-deposition coating has a long crack initiation time, the initiation of cracks is frequent and dispersive, and with the increase of the number of thermal impact, several small cracks finally merge into one place and penetrate through the substrate after 59 times of thermal impact, but the cracks do not extend horizontally at the interface of the film base, and the whole deposition layer does not fall off, indicating that Si-B-Y co-deposition coating can improve the thermal impact property of the TiAlNb9 alloy to a certain extent.

Key words: TiAlNb9 alloy, pack cementation process, Si-B-Y co-deposition coating, thermal impact property

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