EFFECTS OF SN ADDITIONS ON THE MICROSTRUCTURES AND TENSILE PROPERTIESOF 2 PHASE TIAL ALLOYS

Citation
Dn. Wang et al., EFFECTS OF SN ADDITIONS ON THE MICROSTRUCTURES AND TENSILE PROPERTIESOF 2 PHASE TIAL ALLOYS, Intermetallics, 4(3), 1996, pp. 191-200
Citations number
16
Categorie Soggetti
Metallurgy & Metallurigical Engineering","Chemistry Physical","Material Science
Journal title
ISSN journal
09669795
Volume
4
Issue
3
Year of publication
1996
Pages
191 - 200
Database
ISI
SICI code
0966-9795(1996)4:3<191:EOSAOT>2.0.ZU;2-E
Abstract
Effects of Sn additions on the tensile properties of two-phase TiAl al loys in the lamellar form have been investigated in the hope that the tensile ductility of the alloys would be improved by alloying with Sn which is expected to soften the alpha(2) phase and thereby decreases s train incompatibility between the gamma and alpha(2) phases. Microstru ctural observations of the alloys investigated are summarized as follo ws: (i) Ti3Al and Ti3Sn are completely soluble in each other; (ii) a w ide gamma + alpha(2) two-phase field exists in the Ti-Al-Sn system; (i ii) in the two-phase field, the Sn content in the alpha(2) phase is fo ur times higher than that in the gamma phase. Hardness measurements in dicate that the alpha(2) phase is indeed softened when its Sn content exceeds 10 at%, whereas the hardness of the gamma phase increases with increasing Sn content. All these results are in line with our predict ions. However, any significant improvement in tensile ductility has no t been observed upon alloying binary two-phase TiAl alloys with Sn. Po ssible reasons for this are discussed based on the results obtained.