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Advances in Materials Research Volume 1, Number 1, March 2012 , pages 13-29 DOI: https://doi.org/10.12989/amr.2012.1.1.013 |
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High performance ultrafine-grained Ti-Fe-based alloys with multiple length-scale phases |
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Lai-Chang Zhang
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| Abstract | ||
| In order to simultaneously enhance the strength and plasticity in nanostructured / ultrafinegrained alloys, a strategy of introducing multiple length scales into microstructure (or called bimodal composite microstructure) has been developed recently. This paper presents a brief overview of the alloy developement and the mechanical behavior of ultrafine-grained Ti-Fe-based alloys with different lengthscale phases, i.e., micrometer-sized primary phases (dendrites or eutectic) embedded in an ultrafinegrained eutectic matrix. These ultrafine-grained titanium bimodal composites could be directly obtained through a simple single-step solidification process. The as-prepared composites exhibit superior mechanical properties, including high strength of 2000-2700 MPa, large plasticity up to 15-20% and high specific strength. Plastic deformation of the ultrafine-grained titanium bimodal composites occurs through a combination of dislocation-based slip in the nano-/ultrafine scale matrix and constraint multiple shear banding around the micrometer-sized primary phase. The microstructural charactersitcs associated to the mechanical behaivor have been detailed discussed. | ||
| Key Words | ||
| titanium alloy; bimodal composite; multiple length scales; ultrafine-grained; mechanical behavior; microstructure | ||
| Address | ||
| School of Mechanical and Chemical Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, Perth, WA 6009, Australia | ||
