A study on the development of Ni-based alloys with wide supercooled liquidregion

Citation
Jk. Lee et al., A study on the development of Ni-based alloys with wide supercooled liquidregion, MATER TRANS, 42(4), 2001, pp. 592-596
Citations number
15
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Material Science & Engineering
Journal title
MATERIALS TRANSACTIONS
ISSN journal
1345-9678 → ACNP
Volume
42
Issue
4
Year of publication
2001
Pages
592 - 596
Database
ISI
SICI code
1345-9678(200104)42:4<592:ASOTDO>2.0.ZU;2-M
Abstract
Ni-based amorphous alloys with wide supercooled liquid region (DeltaT(X)) h ave been developed through alloy design based upon the empirical rules for high glass forming alloys. The amorphous Ni59Zr20Ti21 alloy shows glass tra nsition temperature of 794 K, onset temperature of the first exotherm (T-X1 ) of 808 K and supercooled liquid range (DeltaT(X) = T-x1 - T-g) of 14 K, w hile the amorphous Ni59Zr20Ti16Si5 alloy shows T-g of 830 K, T-x1 of 576 K and DeltaT(x) of 46 K. The amorphous Ni59Zr20Ti21 and Ni59Zr20Ti16Si5 alloy s crystallize through two step reactions. First, primary crystallization of cubic NiTi(Zr) phase occurs from the amorphous matrix and then the NiTi(Zr ) and remaining amorphous phases transforms into a mixture of cubic NiTi(Zr ) and orthorhombic Ni-10(Zr,Ti)(7) phase for the ternary alloy and into a m ixture of the cubic NiTi(Zr), orthorhombic Ni-10(Zr, Ti)(7) and an unidenti fied phase containing Si for the quaternary alloy. Partial replacement of T i by Si improves glass forming ability. A bulk amorphous Ni59Zr20Ti16Si5 ro d With 2 mm in diameter is fabricated by injection casting.