Favorable microstructural modulation and enhancement of mechanical properties of Ti–Fe–Nb ultrafine composites

Abstract

Abstract Microstructure evolution and its influence on the mechanical properties of (Ti65.5Fe34.5)100− x Nb x (x = 0, 3, 5 and 7) ultrafine composites has been investigated. The Nb-containing alloys exhibit simultaneously improved compressive mechanical properties, i.e. high yield (1.9–2.2 GPa) and fracture (2.2–2.6 GPa) strength together with large plasticity (6–13%), due to a favorable modulation of their ultrafine eutectic microstructure. The enhanced mechanical properties are strongly related to the length-scale, volume fraction and distribution of proeutectic phase as well as to the refinement and interphase coherency of the alternating ultrafine eutectic layers. Keywords: Ti alloysshear bandsplasticitydeformationstrengthhypereutecticpseudo-binary eutectic Acknowledgement The authors would like to thank S. Pauly, Dr. R. Li and G. Wang for providing technical assistance and stimulating discussions. This work was supported by the Global Research Laboratory Program of the Korea Ministry of Education, Science and Technology.