Interdiffusivity in titanium-tantalum alloys processed at 1473 K

Titanium-tantalum (Ti-Ta) alloys are likely to have a high biocompatibility and corrosion resistance that renders them novel materials of interest for biomedical applications[7, 14, 2]. With high strength and a low elastic modulus, Ti-Ta alloys have attracted attention as candidates for such uses as hip replacements[2]. A current challenge impeding use of these alloys is that, with a melting temperature of 3269 K, homogeneous alloys involving Ta are difficult to produce by conventional melting practice[3]. The objective of this work was to, as most structural changes occur via diffusion, gain insight into this matter through determination of the interdiffusivity in Ti-Ta alloys. A scanning electron microscope was utilized to perform energy dispersive x-ray analysis on Ti-Ta alloy samples in the range of 20 to 60 weight percent (wt %) Ta. A computational model that employed Fick's Second Law was used to extract interdiffusivity values from the data. Interdiffusivity values, which ranged from 4.0. 10-13-Tfor 20 wt % Ta to 3.0. 0-14- for 60 wt % Ta, exhibited a systematic variation with composition. The interdiffusion coefficient was seen to decrease with increasing weight fraction Ta.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Materials Science and Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• Dibbern, Jennifer C

Advisor dc:contributor.advisor

• Samuel M. Allen.

• Materials Science and Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/44821

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/44821