[T13] Non Ferrous Materials

[15F-T13-04] The Microstruture and Mechanical Properties of Ti-6Al-4V Alloys Using Hydride–Dehydride (HDH) Powder

*X. Li^{1, 2}, Z. Feng^{1, 2}, F. Yang^{1, 2}, C. Chen^{1, 2}, Z. Guo^{1, 2} (1.University of Science and Technology Beijing, China, 2.Southern Marine Science and Engineering Guangdong Laboratory, China)

Keywords:Ti alloys, oxygen, mechanical propertities

Ti alloys produced from HDH powder has suffered from high O/N interstitials content. In the present study, a whole well-protected process from Ti sponge to as-sintered materials is adopted, and thus the lowest O/N contents of as-sintered materials are 0.07 wt.% and 0.018 wt.%, within the specification of Grade F-23 (Ti-6Al-4V ELI) according to ASTM B988-13. The law of powder and its compact passivation has also been studied in detail. Subsequently, sintering experiment indicates fine ELI powder has an excellent sinterability. A relative density over 96% can be obtained by sintering at 1100 °C. Capsule-free HIP post-sintering achieve full density and obtain fine and near-equiaxed a grain at the same time. The as-HIPped sample has better comprehensive mechanical properties, with strength exceeding 970 MPa and the elongation exceeding 16.4%.