Microstructures and Mechanical Properties of Ti-48Al-2Cr-2Nb-xW


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The microstructures and mechanical properties of three powder metallurgy Ti-48Al-2Cr- 2Nb-xW alloys (where x=0, 0.5, and 1 atomic percent (at.%)) are presented. The results indicate that a solution heat treatment combined with controlled cooling generate a fully lamellar (FL) microstructure without the formation of detrimental Widmanstätten or massively transformed γ phases. Aging causes coarsening of the FL microstructure in the alloys containing 0%W and 0.5%W, while almost no coarsening occurs in the 1%W sample. The addition of W to the base composition results in the formation of precipitates at the lamellar interfaces and grain boundaries during aging which helps stabilize the FL microstructure. The amount of W and the aging time affect the room temperature hardness values and tensile properties.



Materials Science Forum (Volumes 561-565)

Main Theme:

Edited by:

Young Won Chang, Nack J. Kim and Chong Soo Lee




D. Y. Seo et al., "Microstructures and Mechanical Properties of Ti-48Al-2Cr-2Nb-xW", Materials Science Forum, Vols. 561-565, pp. 481-486, 2007

Online since:

October 2007




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