微量TiC掺杂对Mo–Y<sub>2</sub>O<sub>3</sub>合金组织的细化和第二相粒子的调控

扈伟强; 宫凤鸣; 刘少存; 谭晶; 陈松华; 王辉; 马宗青

doi:10.1007/s12613-022-2462-z

Volume 29 Issue 11

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文章导航 > 矿物冶金与材料学报（英文） > 2022 > 29(11): 2012-2019

Weiqiang Hu, Fengming Gong, Shaocun Liu, Jing Tan, Songhua Chen, Hui Wang, and Zongqing Ma, Microstructure refinement and second phase particle regulation of Mo–Y₂O₃ alloys by minor TiC additive, Int. J. Miner. Metall. Mater., 29(2022), No. 11, pp. 2012-2019. https://doi.org/10.1007/s12613-022-2462-z

Cite this article as:

Weiqiang Hu, Fengming Gong, Shaocun Liu, Jing Tan, Songhua Chen, Hui Wang, and Zongqing Ma, Microstructure refinement and second phase particle regulation of Mo–Y2O3 alloys by minor TiC additive, Int. J. Miner. Metall. Mater., 29(2022), No. 11, pp. 2012-2019. https://doi.org/10.1007/s12613-022-2462-z

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研究论文

微量TiC掺杂对Mo–Y₂O₃合金组织的细化和第二相粒子的调控

1)
天津大学材料科学与工程学院，天津市材料复合与功能化重点实验室，天津 300072，中国
2)
中国石油工程项目管理公司天津设计院，天津 300457，中国
3)
龙岩学院化学与材料科学学院，龙岩 364012，中国
4)
成都大学机械工程学院，成都 610106，中国

通讯作者:
马宗青 E-mail: mzq0320@163.com

文章亮点

(1) 研究了Y₂O₃和TiC复合掺杂对Mo–Y₂O₃合金微观组织、性能的影响。

(2) 揭示了Y₂O₃和TiC复合掺杂能细化基体和第二相的机理。

(3) 基于第二相成分提出了一个基体净化和强化的理论。

中文摘要

氧化物弥散强化的钼合金具有很多优异的力学性能，在高温合金领域具有很大的吸引力。然而传统球磨及后续烧结工艺制备的氧化物弥散强化Mo合金(ODS-Mo)的Mo晶粒较粗，Mo晶界处的氧化物颗粒也较大，这明显抑制了氧化物加入的强化效果。在这项工作中，我们通过球磨和随后的低温烧结，将Y₂O₃和TiC颗粒同时掺杂到Mo合金中。随着TiC的加入，Mo–Y₂O₃晶粒由3.12 μm急剧细化到1.36 μm。特别是，与单独掺杂的Y₂O₃颗粒(~420 nm)相比，共掺杂的Y₂O₃和TiC在Mo晶界上能形成更小的Y–Ti–O–C第四相颗粒(~230 nm)，从而能更有效地固定和阻碍晶界的运动。除了晶界上的Y–Ti–O–C颗粒外，Mo颗粒中还存在Y₂O₃、TiO_x和TiC_x纳米颗粒(<100 nm)，这与传统的ODS-Mo有显著不同。TiO_x相的出现表明，TiC中的一些活性Ti吸附Mo基体中的氧杂质形成新的强化相，从而对Mo基体进行强化和净化。纯Mo、Mo–Y₂O₃和Mo–Y₂O₃– TiC合金具有相似的相对密度(97.4%–98.0%)。更重要的是，Mo–Y₂O₃–TiC合金的硬度(HV_0.2 (425 ± 25))高于Mo–Y₂O₃合金(HV_0.2 (370 ± 25))。本研究为球磨法制备超细Mo合金提供了相关的策略。

关键词:

Research Article

Microstructure refinement and second phase particle regulation of Mo–Y₂O₃ alloys by minor TiC additive

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Abstract

Abstract

The oxide dispersion strengthened Mo alloys (ODS-Mo) prepared by traditional ball milling and subsequent sintering technique generally possess comparatively coarse Mo grains and large oxide particles at Mo grain boundaries (GBs), which obviously suppress the corresponding strengthening effect of oxide addition. In this work, the Y₂O₃ and TiC particles were simultaneously doped into Mo alloys using ball-milling and subsequent low temperature sintering. Accompanied by TiC addition, the Mo–Y₂O₃ grains are sharply refined from 3.12 to 1.36 μm. In particular, Y₂O₃ and TiC can form smaller Y–Ti–O–C quaternary phase particles (~230 nm) at Mo GBs compared to single Y₂O₃ particles (~420 nm), so as to these new formed Y–Ti–O–C particles can more effectively pin and hinder GBs movement. In addition to Y–Ti–O–C particles at GBs, Y₂O₃, TiO_x, and TiC_x nanoparticles (<100 nm) also exist within Mo grains, which is significantly different from traditional ODS-Mo. The appearance of TiO_x phase indicates that some active Ti within TiC can adsorb oxygen impurities of Mo matrix to form a new strengthening phase, thus strengthening and purifying Mo matrix. Furthermore, the pure Mo, Mo–Y₂O₃, and Mo–Y₂O₃–TiC alloys have similar relative densities (97.4%–98.0%). More importantly, the Mo–Y₂O₃–TiC alloys exhibit higher hardness (HV_0.2 (425 ± 25)) compared to Mo–Y₂O₃ alloys (HV_0.2 (370 ± 25)). This work could provide a relevant strategy for the preparation of ultrafine Mo alloys by facile ball-milling.
- Mo–Y₂O₃–TiC alloys;
- ball-milling;
- low temperature sintering;
- ultrafine grains;
- high hardness

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微量TiC掺杂对Mo–Y₂O₃合金组织的细化和第二相粒子的调控

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Microstructure refinement and second phase particle regulation of Mo–Y₂O₃ alloys by minor TiC additive

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微量TiC掺杂对Mo–Y2O3合金组织的细化和第二相粒子的调控

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Microstructure refinement and second phase particle regulation of Mo–Y2O3 alloys by minor TiC additive

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微量TiC掺杂对Mo–Y₂O₃合金组织的细化和第二相粒子的调控

Microstructure refinement and second phase particle regulation of Mo–Y₂O₃ alloys by minor TiC additive