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Title: In situ design of advanced titanium alloy with concentration modulations by additive manufacturing
Additive manufacturing is a revolutionary technology that offers a different pathway for material processing and design. However, innovations in either new materials or new processing technologies can seldom be successful without a synergistic combination. We demonstrate an in situ design approach to make alloys spatially modulated in concentration by using laser-powder bed fusion. We show that the partial homogenization of two dissimilar alloy melts—Ti-6Al-4V and a small amount of 316L stainless steel—allows us to produce micrometer-scale concentration modulations of the elements that are contained in 316L in the Ti-6Al-4V matrix. The corresponding phase stability modulation creates a fine scale–modulated β + α′ dual-phase microstructure that exhibits a progressive transformation-induced plasticity effect, which leads to a high tensile strength of ~1.3 gigapascals with a uniform elongation of ~9% and an excellent work-hardening capacity of >300 megapascals. This approach creates a pathway for concentration-modulated heterogeneous alloy design for structural and functional applications.
Authors:
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Award ID(s):
1923929
Publication Date:
NSF-PAR ID:
10326081
Journal Name:
Science
Volume:
374
Issue:
6566
Page Range or eLocation-ID:
478 to 482
ISSN:
0036-8075
Sponsoring Org:
National Science Foundation
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