Formation mechanism of an α2 phase-rich layer on the surface of Ti-22Al-25Nb alloy

Bin Shao; Shengxiang Wan; Wenchen Xu; Debin Shan; Bin Guo; Yingying Zong

doi:10.1016/j.matchar.2018.08.030

Formation mechanism of an α₂ phase-rich layer on the surface of Ti-22Al-25Nb alloy

Bin Shao
, Shengxiang Wan
, Wenchen Xu
, Debin Shan
, Bin Guo
, Yingying Zong^*

^*Corresponding author for this work

School of Materials Science and Engineering

Harbin Institute of Technology

Research output: Contribution to journal › Article › peer-review

15 Scopus citations

Abstract

In order to investigate the formation mechanism of the α₂-rich layer in the surface of the Ti-22Al-25Nb alloy, systematic analyses are carried out on the surface of the alloy by using SEM, XRD and EBSD. The results reveal that this α₂-rich layer is formed by oxidation of the surface layer. In this surface oxidation layer, there are abundant Ti₂O₃ particles similar with the α₂ phase in structure. These Ti₂O₃ particles serve as nucleation points and lower the nucleation energy of the α₂ phase, promoting the precipitation and growth of α₂ phase on the surface layer of the alloy. This surface layer has a hardness of 684 HV, significantly exceeding the value of 312 HV for the interior of the alloy and thus considerably improves the surface properties of the alloy, serving as a high-performance, self-generated surface strengthening layer.

Original language	English
Pages (from-to)	205-209
Number of pages	5
Journal	Materials Characterization
Volume	145
DOIs	https://doi.org/10.1016/j.matchar.2018.08.030
State	Published - Nov 2018

Keywords

Oxidation
Surfaces
Titanium aluminides
α phase

Access to Document

10.1016/j.matchar.2018.08.030

Cite this

@article{27d36cbc4a6b4f60a6cdad8d7d1f5f5f,

title = "Formation mechanism of an α2 phase-rich layer on the surface of Ti-22Al-25Nb alloy",

abstract = "In order to investigate the formation mechanism of the α2-rich layer in the surface of the Ti-22Al-25Nb alloy, systematic analyses are carried out on the surface of the alloy by using SEM, XRD and EBSD. The results reveal that this α2-rich layer is formed by oxidation of the surface layer. In this surface oxidation layer, there are abundant Ti2O3 particles similar with the α2 phase in structure. These Ti2O3 particles serve as nucleation points and lower the nucleation energy of the α2 phase, promoting the precipitation and growth of α2 phase on the surface layer of the alloy. This surface layer has a hardness of 684 HV, significantly exceeding the value of 312 HV for the interior of the alloy and thus considerably improves the surface properties of the alloy, serving as a high-performance, self-generated surface strengthening layer.",

keywords = "Oxidation, Surfaces, Titanium aluminides, α phase",

author = "Bin Shao and Shengxiang Wan and Wenchen Xu and Debin Shan and Bin Guo and Yingying Zong",

note = "Publisher Copyright: {\textcopyright} 2018 Elsevier Inc.",

year = "2018",

month = nov,

doi = "10.1016/j.matchar.2018.08.030",

language = "英语",

volume = "145",

pages = "205--209",

journal = "Materials Characterization",

issn = "1044-5803",

publisher = "Elsevier Inc.",

}

TY - JOUR

T1 - Formation mechanism of an α2 phase-rich layer on the surface of Ti-22Al-25Nb alloy

AU - Shao, Bin

AU - Wan, Shengxiang

AU - Xu, Wenchen

AU - Shan, Debin

AU - Guo, Bin

AU - Zong, Yingying

PY - 2018/11

Y1 - 2018/11

N2 - In order to investigate the formation mechanism of the α2-rich layer in the surface of the Ti-22Al-25Nb alloy, systematic analyses are carried out on the surface of the alloy by using SEM, XRD and EBSD. The results reveal that this α2-rich layer is formed by oxidation of the surface layer. In this surface oxidation layer, there are abundant Ti2O3 particles similar with the α2 phase in structure. These Ti2O3 particles serve as nucleation points and lower the nucleation energy of the α2 phase, promoting the precipitation and growth of α2 phase on the surface layer of the alloy. This surface layer has a hardness of 684 HV, significantly exceeding the value of 312 HV for the interior of the alloy and thus considerably improves the surface properties of the alloy, serving as a high-performance, self-generated surface strengthening layer.

AB - In order to investigate the formation mechanism of the α2-rich layer in the surface of the Ti-22Al-25Nb alloy, systematic analyses are carried out on the surface of the alloy by using SEM, XRD and EBSD. The results reveal that this α2-rich layer is formed by oxidation of the surface layer. In this surface oxidation layer, there are abundant Ti2O3 particles similar with the α2 phase in structure. These Ti2O3 particles serve as nucleation points and lower the nucleation energy of the α2 phase, promoting the precipitation and growth of α2 phase on the surface layer of the alloy. This surface layer has a hardness of 684 HV, significantly exceeding the value of 312 HV for the interior of the alloy and thus considerably improves the surface properties of the alloy, serving as a high-performance, self-generated surface strengthening layer.

KW - Oxidation

KW - Surfaces

KW - Titanium aluminides

KW - α phase

UR - https://www.scopus.com/pages/publications/85052490010

U2 - 10.1016/j.matchar.2018.08.030

DO - 10.1016/j.matchar.2018.08.030

M3 - 文章

AN - SCOPUS:85052490010

SN - 1044-5803

VL - 145

SP - 205

EP - 209

JO - Materials Characterization

JF - Materials Characterization

ER -

Formation mechanism of an α₂ phase-rich layer on the surface of Ti-22Al-25Nb alloy

Abstract

Keywords

Access to Document

Other files and links

Fingerprint

Cite this