+高级检索
铸态Ti-22Al-25Nb合金的结构特征与力学性能
作者:
作者单位:

南京理工大学

作者简介:

通讯作者:

中图分类号:

TG294

基金项目:

国家自然科学基金项目(面上项目,重点项目,重大项目)


Structural features and mechanical properties of as-cast Ti-22Al-25Nb alloy
Author:
Affiliation:

School of Mechanical Engineering,Nanjing University of Science and Technology

Fund Project:

The National Natural Science Foundation of China (General Program, Key Program, Major Research Plan)

  • 摘要
  • |
  • 图/表
  • |
  • 访问统计
  • |
  • 参考文献
  • |
  • 相似文献
  • |
  • 引证文献
  • |
  • 资源附件
  • |
  • 文章评论
    摘要:

    Ti2AlNb基合金是目前有望在650-800℃温度范围内取代高温镍基合金的金属间化合物。利用水冷铜坩埚感应悬浮熔炼法,通过调控熔炼工艺,制备了主相分别为B2/?相和O相 Ti-22Al-25Nb合金铸锭,通过XRD、SEM等手段进行了合金结构特征的表征,通过室温拉伸试验、室温压缩试验、纳米压痕试验测试了合金的力学性能并分析了断口形貌。研究表明,铸态Ti-22Al-25Nb合金晶粒尺寸达到数百微米。相组成对铸态Ti-22Al-25Nb合金的力学性能有一定影响,铸态O相合金的极限抗拉强度达到了1125MPa,超过了铸态B2/?相合金的1031MPa,但粗大晶粒导致合金塑性较差(铸态B2/?相与铸态O相合金的延伸率分布为1.82%与1.32%)。铸态Ti-22Al-25Nb合金的拉伸断口与压缩断口均具有明显的解理断裂特征,拉伸断口主要表现为沿晶断裂,压缩断口主要表现为穿晶断裂。

    Abstract:

    Ti2AlNb-based alloy is a kind of intermetallic compound. It is expected to replace Ni-based superalloys for high-temperature structural applications with a temperature range of 650-800 ℃. In this work, a Ti2AlNb based alloy with a nominal composition of Ti-22Al-25Nb is prepared by water-cooled copper crucible induction floating melting method. The structural features of the as-cast Ti-22Al-25Nb alloy are characterized by XRD and SEM. It is found that the main phase of the as-cast Ti-22Al-25Nb alloy can be B2/? phase or O phase, depending on its melting and casting process parameters. The grain size of the as-cast Ti-22Al-25Nb alloy reaches several hundred microns. The mechanical properties of the as-cast Ti-22Al-25Nb alloy are investigated by tensile, compressive and nanoindentation tests at room temperature. The ultimate tensile strength of the as-cast Ti-22Al-25Nb O phase alloy and B2/? alloy reaches 1125 MPa and 1031 MPa respectively, with the elongation of 1.32% and 1.82%. The nanoindentation hardness of the as-cast Ti-22Al-25Nb O phase alloy is slightly higher than that of the as-cast B2/? phase alloy. The tensile fracture and compression fracture of as-cast Ti-22Al-25Nb alloy show obvious cleavage fracture characteristics. In addition, the tensile fracture is mainly intergranular, while the compression fracture is mainly transgranular.

    参考文献
    相似文献
    引证文献
引用本文

杨龙川,苏艳,杜宇雷,廖文和.铸态Ti-22Al-25Nb合金的结构特征与力学性能[J].稀有金属材料与工程,2020,49(11):3902~3908.[Yang Longchuan, Su Yan, Du Yulei, Liao Wenhe. Structural features and mechanical properties of as-cast Ti-22Al-25Nb alloy[J]. Rare Metal Materials and Engineering,2020,49(11):3902~3908.]
DOI:10.12442/j. issn.1002-185X.20190991

复制
文章指标
  • 点击次数:
  • 下载次数:
  • HTML阅读次数:
  • 引用次数:
历史
  • 收稿日期:2019-11-26
  • 最后修改日期:2019-12-17
  • 录用日期:2020-01-03
  • 在线发布日期: 2020-12-09
  • 出版日期: