Phase separation in TiAl(L10)-(Al, Cr)3Ti(L12) system

Keiichiro Oh-ishi, Hideki Kumamoto, Zenji Horita, Minoru Nemoto

Research output: Contribution to journalArticle

Abstract

Hardness and microstructural variations during aging of Ti-Al-Cr ternary L10- and L12-phase alloys have been investigated in terms of hardness measurements and transmission electron microscopy. Both the L10 and L12 phase alloys harden by aging at 973 K after solution annealing at higher temperatures. The amount of age hardening of the L12 phase alloy is larger than that of the L10 phase alloy. The phase separation between L10 and L12 phase have not been observed by aging at 973 K. But Al2Ti was formed in each matrix alloy during aging. The crystal structure of the Al2Ti phase is a Ga2Zr type in the L10 and a Ga2Hf type in the L12 phase, respectively. At the beginning of aging the fine coherent cuboidal Al2Ti-phase are formed in the L10 phase. By further aging, two variants of Al2Ti precipitates grow along the two {110} habit planes. On the other hand, in the L12 phase, the Al2Ti phase forms on the {100} planes of the L12 matrix lattice. After prolonged aging the precipitates are rearranged along a preferential direction of the matrix lattice and form a domain consisting of only one variant. It is suggested that the precipitation of Al2Ti in each matrix alloy occurs to form a morphology which efficiently relaxes the elastic strain between precipitate and matrix lattices.

Original languageEnglish
Pages (from-to)609-615
Number of pages7
JournalNippon Kinzoku Gakkaishi/Journal of the Japan Institute of Metals
Volume64
Issue number8
DOIs
Publication statusPublished - Jan 1 2000

Fingerprint

Phase separation
Aging of materials
matrices
Precipitates
precipitates
hardness
Hardness
precipitation hardening
Age hardening
habits
Crystal structure
Annealing
Transmission electron microscopy
transmission electron microscopy
crystal structure
annealing

All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics
  • Mechanics of Materials
  • Metals and Alloys
  • Materials Chemistry

Cite this

Phase separation in TiAl(L10)-(Al, Cr)3Ti(L12) system. / Oh-ishi, Keiichiro; Kumamoto, Hideki; Horita, Zenji; Nemoto, Minoru.

In: Nippon Kinzoku Gakkaishi/Journal of the Japan Institute of Metals, Vol. 64, No. 8, 01.01.2000, p. 609-615.

Research output: Contribution to journalArticle

Oh-ishi, Keiichiro ; Kumamoto, Hideki ; Horita, Zenji ; Nemoto, Minoru. / Phase separation in TiAl(L10)-(Al, Cr)3Ti(L12) system. In: Nippon Kinzoku Gakkaishi/Journal of the Japan Institute of Metals. 2000 ; Vol. 64, No. 8. pp. 609-615.
@article{de2f298990ad4493a390045410221902,
title = "Phase separation in TiAl(L10)-(Al, Cr)3Ti(L12) system",
abstract = "Hardness and microstructural variations during aging of Ti-Al-Cr ternary L10- and L12-phase alloys have been investigated in terms of hardness measurements and transmission electron microscopy. Both the L10 and L12 phase alloys harden by aging at 973 K after solution annealing at higher temperatures. The amount of age hardening of the L12 phase alloy is larger than that of the L10 phase alloy. The phase separation between L10 and L12 phase have not been observed by aging at 973 K. But Al2Ti was formed in each matrix alloy during aging. The crystal structure of the Al2Ti phase is a Ga2Zr type in the L10 and a Ga2Hf type in the L12 phase, respectively. At the beginning of aging the fine coherent cuboidal Al2Ti-phase are formed in the L10 phase. By further aging, two variants of Al2Ti precipitates grow along the two {110} habit planes. On the other hand, in the L12 phase, the Al2Ti phase forms on the {100} planes of the L12 matrix lattice. After prolonged aging the precipitates are rearranged along a preferential direction of the matrix lattice and form a domain consisting of only one variant. It is suggested that the precipitation of Al2Ti in each matrix alloy occurs to form a morphology which efficiently relaxes the elastic strain between precipitate and matrix lattices.",
author = "Keiichiro Oh-ishi and Hideki Kumamoto and Zenji Horita and Minoru Nemoto",
year = "2000",
month = "1",
day = "1",
doi = "10.2320/jinstmet1952.64.8_609",
language = "English",
volume = "64",
pages = "609--615",
journal = "Nippon Kinzoku Gakkaishi/Journal of the Japan Institute of Metals",
issn = "0021-4876",
publisher = "公益社団法人 日本金属学会",
number = "8",

}

TY - JOUR

T1 - Phase separation in TiAl(L10)-(Al, Cr)3Ti(L12) system

AU - Oh-ishi, Keiichiro

AU - Kumamoto, Hideki

AU - Horita, Zenji

AU - Nemoto, Minoru

PY - 2000/1/1

Y1 - 2000/1/1

N2 - Hardness and microstructural variations during aging of Ti-Al-Cr ternary L10- and L12-phase alloys have been investigated in terms of hardness measurements and transmission electron microscopy. Both the L10 and L12 phase alloys harden by aging at 973 K after solution annealing at higher temperatures. The amount of age hardening of the L12 phase alloy is larger than that of the L10 phase alloy. The phase separation between L10 and L12 phase have not been observed by aging at 973 K. But Al2Ti was formed in each matrix alloy during aging. The crystal structure of the Al2Ti phase is a Ga2Zr type in the L10 and a Ga2Hf type in the L12 phase, respectively. At the beginning of aging the fine coherent cuboidal Al2Ti-phase are formed in the L10 phase. By further aging, two variants of Al2Ti precipitates grow along the two {110} habit planes. On the other hand, in the L12 phase, the Al2Ti phase forms on the {100} planes of the L12 matrix lattice. After prolonged aging the precipitates are rearranged along a preferential direction of the matrix lattice and form a domain consisting of only one variant. It is suggested that the precipitation of Al2Ti in each matrix alloy occurs to form a morphology which efficiently relaxes the elastic strain between precipitate and matrix lattices.

AB - Hardness and microstructural variations during aging of Ti-Al-Cr ternary L10- and L12-phase alloys have been investigated in terms of hardness measurements and transmission electron microscopy. Both the L10 and L12 phase alloys harden by aging at 973 K after solution annealing at higher temperatures. The amount of age hardening of the L12 phase alloy is larger than that of the L10 phase alloy. The phase separation between L10 and L12 phase have not been observed by aging at 973 K. But Al2Ti was formed in each matrix alloy during aging. The crystal structure of the Al2Ti phase is a Ga2Zr type in the L10 and a Ga2Hf type in the L12 phase, respectively. At the beginning of aging the fine coherent cuboidal Al2Ti-phase are formed in the L10 phase. By further aging, two variants of Al2Ti precipitates grow along the two {110} habit planes. On the other hand, in the L12 phase, the Al2Ti phase forms on the {100} planes of the L12 matrix lattice. After prolonged aging the precipitates are rearranged along a preferential direction of the matrix lattice and form a domain consisting of only one variant. It is suggested that the precipitation of Al2Ti in each matrix alloy occurs to form a morphology which efficiently relaxes the elastic strain between precipitate and matrix lattices.

UR - http://www.scopus.com/inward/record.url?scp=0033666061&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0033666061&partnerID=8YFLogxK

U2 - 10.2320/jinstmet1952.64.8_609

DO - 10.2320/jinstmet1952.64.8_609

M3 - Article

AN - SCOPUS:0033666061

VL - 64

SP - 609

EP - 615

JO - Nippon Kinzoku Gakkaishi/Journal of the Japan Institute of Metals

JF - Nippon Kinzoku Gakkaishi/Journal of the Japan Institute of Metals

SN - 0021-4876

IS - 8

ER -