Phase Evaluation in Al(2)O(3) Fiber-Reinforced Ti(2)AlC During Sintering in the 1300 degrees C-1500 degrees C Temperature Range
2011 (English)In: Journal of The American Ceramic Society, ISSN 0002-7820, E-ISSN 1551-2916, Vol. 94, no 10, 3327-3334 p.Article in journal (Refereed) Published
In this article, the reactivity of Ti(2)AlC powders, with 3 and 10 mu m alumina, Al(2)O(3), fibers during pressure-assisted sintering is explored. Samples were fabricated by hot-isostatic-pressing (HIPed) or hot-pressing (HPed), and characterized by X-ray diffraction, differential thermal analysis, and electron microscopy-both scanning and transmission-equipped with energy dispersive X-ray spectroscopes. Samples prepared at 1300 degrees C were fully dense, with no apparent reaction between fiber and matrix. In samples HPed to 1500 degrees C, even pure Ti(2)AlC powders dissociated to Ti(3)AlC(2) according to: 2 Ti(2)AlC = Ti(3)AlC(2) + TiAl(x) (l) + (1-x) Al (l/v), with x andlt; 1. More severe Al loss results in the formation of TiC(y). The presence of the Al(2)O(3) fibers delayed densification enough to allow most of the Al and some of the Ti to escape into the vacuum of the hot press or react with the encapsulating glass during HIPing a resulting in a more intensive dissociation of the Ti(2)AlC. Although, in principle Ti(2)AlC can be reinforced with Al(2)O(3) fibers, the processing/use temperature will have to be kept below 1500 degrees C, as, at that temperature the fibers, used here, sinter together.
Place, publisher, year, edition, pages
Wiley-Blackwell , 2011. Vol. 94, no 10, 3327-3334 p.
IdentifiersURN: urn:nbn:se:liu:diva-72032DOI: 10.1111/j.1551-2916.2011.04612.xISI: 000295524300035OAI: oai:DiVA.org:liu-72032DiVA: diva2:455984
Funding Agencies|Army Research Office|W911NF-07-1-0628|Metals Division of the NSF|SGER 0736218|Air Force Office of Scientific Research|FA9550-09-1-0686|Swedish Foundation for Strategic Research (SSF)||2011-11-112011-11-112013-10-02