Microstructural control of TiAl–Mo–B alloys by directional solidification

✍ Scribed by D.R. Johnson; K. Chihara; H. Inui; M. Yamaguchi

• Book ID: 104403728
• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 1016 KB
• Volume: 46
• Category: Article
• ISSN: 1359-6454
• DOI: 10.1016/s1359-6454(98)00310-3

✦ Synopsis

AbstractÐDirectional solidi®cation experiments were performed to see if the g/a 2 lamellar boundaries could be aligned parallel to the growth direction for an ingot containing columnar lamellar grains. From microstructural analysis of arc-melted ingots, a projection of the partial liquidus surface for the Ti±Al±Mo system was constructed and this was used with an analytical description of the phase diagram to calculate the solidi®cation paths. Following this analysis, Ti±Al±Mo(+B) ingots were directionally solidi®ed at growth rates between 40 and 100 mm/h. By controlling the solidi®cation path, a possible processing window where a reasonably well aligned g/a 2 microstructure can be produced was identi®ed. As-processed microstructures exhibited a compressive yield strength greater than 500 MPa at 8008C and 2% ductility at room temperature.