Ni3Al and Ni3Si-based intermetallics produced by the Osprey process
| Autor: | A. Tamminen, M.-M. Riipinen, R. Rautioaho, T. Saven |
|---|---|
| Rok vydání: | 1996 |
| Předmět: |
Materials science
Mechanical Engineering Metallurgy Alloy Metals and Alloys Analytical chemistry Intermetallic chemistry.chemical_element General Chemistry engineering.material Microstructure Chromium chemistry Mechanics of Materials Impurity Phase (matter) Materials Chemistry engineering Grain boundary Lamellar structure |
| Zdroj: | Intermetallics. 4:99-109 |
| ISSN: | 0966-9795 |
| DOI: | 10.1016/0966-9795(95)00022-4 |
| Popis: | Four NiAlbased and two NiSiTibased intermetallic compounds were spray-deposited using a nitrogen gas for atomization. The impurity contents, relative densities and microstructures of the alloys were investigated in the as-deposited condition.The oxygen content of the alloys varied from 20 to 90 ppm, and the nitrogen content ranged from 10 ppm in a binary Ni3AI compound to 90 ppm in NiAlCrFe alloy and to 150 ppm in the case of NiSiTi. No sign of nitrides or oxides was observed. The relative density of the alloys was higher than 99% and the majority of pores located at grain boundaries. The chromium free NiAI alloy had a single-phase, equiaxed and recrystallized structure (γ′), while the chromium containing NiAI alloys had a γγ′ multiphase structure with 5–20% volume fraction of the disordered γ phase. The γ phase formed a network or a bimodal mixture of network and lamellar structures in the ordered γ′ matrix. The NiSiTi alloys showed a cell structure with cell interiors consisting of γγ′ network structure and cell borders of the ordered γ′ phase. The mechanical properties were comparable with those of the previously spray-deposited Ni3Al-based alloys or with those of the NiSiTi based alloys of the present type. |
| Databáze: | OpenAIRE |
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