Hydride formation in two-phase (Ti3Al + TiAl) titanium aluminides during cathodic charging and its dissociation

Akito Takasaki, Kozo Ojima, Youji Taneda

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

A (TiAl)Hx hydride which has a tetragonal crystal structure with lattice parameters a = 0.452 nm and c = 0.326 nm (c/a = 0.721) has been observed in Ti42Al, Ti45Al and Ti50Al (at.%) two-phase (Ti3Al (α2) + TiAl (γ)) titanium aluminides by cathodic charging in a 5% H2SO4 solution. Cracks or pits are also observed within the γ phase regions in the two-phase (α2 + γ) coexisting grains (such as lamellar grains) but not within the α2 phase or single γ grains. Weights of the samples decrease with increasing charging time owing to the crack or pit formation, and this is more drastic in the Ti-50Al alloy than in the Ti-42Al and Ti-45Al alloys. The hydride is thermally stable at temperatures up to about 550 K (277 °C) and dissociates completely at temperatures between 673 K (400 °C) and 723 K (450 °C).

Original languageEnglish
Pages (from-to)1-6
Number of pages6
JournalJournal of Alloys and Compounds
Volume216
Issue number1
DOIs
Publication statusPublished - 1994
Externally publishedYes

Fingerprint

Titanium
Hydrides
Cracks
Lattice constants
Crystal structure
Temperature

Keywords

  • Cathodic charging
  • Hydride formation
  • Titanium aluminides

ASJC Scopus subject areas

  • Metals and Alloys

Cite this

Hydride formation in two-phase (Ti3Al + TiAl) titanium aluminides during cathodic charging and its dissociation. / Takasaki, Akito; Ojima, Kozo; Taneda, Youji.

In: Journal of Alloys and Compounds, Vol. 216, No. 1, 1994, p. 1-6.

Research output: Contribution to journalArticle

@article{be64013548c74fa7b52da00f26921298,
title = "Hydride formation in two-phase (Ti3Al + TiAl) titanium aluminides during cathodic charging and its dissociation",
abstract = "A (TiAl)Hx hydride which has a tetragonal crystal structure with lattice parameters a = 0.452 nm and c = 0.326 nm (c/a = 0.721) has been observed in Ti42Al, Ti45Al and Ti50Al (at.{\%}) two-phase (Ti3Al (α2) + TiAl (γ)) titanium aluminides by cathodic charging in a 5{\%} H2SO4 solution. Cracks or pits are also observed within the γ phase regions in the two-phase (α2 + γ) coexisting grains (such as lamellar grains) but not within the α2 phase or single γ grains. Weights of the samples decrease with increasing charging time owing to the crack or pit formation, and this is more drastic in the Ti-50Al alloy than in the Ti-42Al and Ti-45Al alloys. The hydride is thermally stable at temperatures up to about 550 K (277 °C) and dissociates completely at temperatures between 673 K (400 °C) and 723 K (450 °C).",
keywords = "Cathodic charging, Hydride formation, Titanium aluminides",
author = "Akito Takasaki and Kozo Ojima and Youji Taneda",
year = "1994",
doi = "10.1016/0925-8388(94)91032-4",
language = "English",
volume = "216",
pages = "1--6",
journal = "Journal of Alloys and Compounds",
issn = "0925-8388",
publisher = "Elsevier BV",
number = "1",

}

TY - JOUR

T1 - Hydride formation in two-phase (Ti3Al + TiAl) titanium aluminides during cathodic charging and its dissociation

AU - Takasaki, Akito

AU - Ojima, Kozo

AU - Taneda, Youji

PY - 1994

Y1 - 1994

N2 - A (TiAl)Hx hydride which has a tetragonal crystal structure with lattice parameters a = 0.452 nm and c = 0.326 nm (c/a = 0.721) has been observed in Ti42Al, Ti45Al and Ti50Al (at.%) two-phase (Ti3Al (α2) + TiAl (γ)) titanium aluminides by cathodic charging in a 5% H2SO4 solution. Cracks or pits are also observed within the γ phase regions in the two-phase (α2 + γ) coexisting grains (such as lamellar grains) but not within the α2 phase or single γ grains. Weights of the samples decrease with increasing charging time owing to the crack or pit formation, and this is more drastic in the Ti-50Al alloy than in the Ti-42Al and Ti-45Al alloys. The hydride is thermally stable at temperatures up to about 550 K (277 °C) and dissociates completely at temperatures between 673 K (400 °C) and 723 K (450 °C).

AB - A (TiAl)Hx hydride which has a tetragonal crystal structure with lattice parameters a = 0.452 nm and c = 0.326 nm (c/a = 0.721) has been observed in Ti42Al, Ti45Al and Ti50Al (at.%) two-phase (Ti3Al (α2) + TiAl (γ)) titanium aluminides by cathodic charging in a 5% H2SO4 solution. Cracks or pits are also observed within the γ phase regions in the two-phase (α2 + γ) coexisting grains (such as lamellar grains) but not within the α2 phase or single γ grains. Weights of the samples decrease with increasing charging time owing to the crack or pit formation, and this is more drastic in the Ti-50Al alloy than in the Ti-42Al and Ti-45Al alloys. The hydride is thermally stable at temperatures up to about 550 K (277 °C) and dissociates completely at temperatures between 673 K (400 °C) and 723 K (450 °C).

KW - Cathodic charging

KW - Hydride formation

KW - Titanium aluminides

UR - http://www.scopus.com/inward/record.url?scp=0028734290&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0028734290&partnerID=8YFLogxK

U2 - 10.1016/0925-8388(94)91032-4

DO - 10.1016/0925-8388(94)91032-4

M3 - Article

VL - 216

SP - 1

EP - 6

JO - Journal of Alloys and Compounds

JF - Journal of Alloys and Compounds

SN - 0925-8388

IS - 1

ER -