Microstructures and Hardness Properties for β-Phase Ti–24Nb–4Zr–7.9Sn Alloy Fabricated by Electron Beam Melting
| Autor: | Ryan B. Wicker, Rui Yang, Y.L. Hao, Fan Yang, Frank Medina, Jennifer Hernandez, Cesar A. Terrazas, Lawrence E Murr, Sara M. Gaytan, Krista Amato, Xuemin Pan, S.J. Li, X. Y. Cheng, E. Martinez |
|---|---|
| Rok vydání: | 2013 |
| Předmět: |
Diffraction
Materials science Polymers and Plastics Scattering Mechanical Engineering Metallurgy Alloy Metals and Alloys engineering.material Microstructure law.invention Mechanics of Materials law Transmission electron microscopy Materials Chemistry Ceramics and Composites engineering Orthorhombic crystal system Electron microscope Selected area diffraction Composite material |
| Zdroj: | Journal of Materials Science & Technology. 29:1011-1017 |
| ISSN: | 1005-0302 |
| Popis: | Atomized, pre-alloyed Ti–24Nb–4Zr–7.9Sn (wt%) powder was used to fabricate solid, prototype components by electron beam melting (EBM). Vickers microindentation hardness values were observed to average 2 GPa for the precursor powder and 2.5 GPa for the solid, EBM-fabricated products. The powder and solid product microstructures were examined by optical and electron microscopy. X-ray diffraction analyses showed that they had bcc β-phase microstructure. However, it was found by transmission electron microscopy that the EBM-fabricated product had plate morphology with space ∼100–200 nm. Although the corresponding selected area diffraction patterns can be indexed by β-phase plus α″-martensite with orthorhombic crystal structure, the dark-field analyses failed to observe the α″-martensite. Such phenomenon was also found in deformed gum metals and explained by stress-induced diffusion scattering due to phonon softening. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect