Abstract
The development of significantly ductile β-NiAl(B2)-based alloys through microstructural control based on phase diagram information is presented. A marked improvement in hot-workability and room temperature tensile properties was realized in the Ni-Al-X (X: Fe, Co, Mn) systems by ensuring the presence of the disordered γ (fcc) phase in the β-phase matrix grain boundaries. Using the same principle, ductile multi-phase alloys with the β phase as the matrix and γ and γ′ (L12) as coexistent phases have also been developed using conventional processing techniques like casting, hot-rolling and heat treatment. It has been observed that the martensitic transformation from β to β′ (L10) has a significant effect on the microstructural features of the β+γ′ alloys. It is shown that possibilities for development of different microstructures through thermo-mechanical treatments as in Fe-based alloys, exist for the nickel-aluminides as well. In this respect it is emphasized that phase diagrams and their calculation using the CALPHAD (Calculation of Phase Diagrams) approach play a significant role in aiding alloy design to improve the ductility of intermetallic alloys through microstructural control.
| Original language | English |
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| Pages | 77-90 |
| Number of pages | 14 |
| Publication status | Published - 1994 |
| Event | Proceedings of the 1994 TMS Fall Symposium - Rosemont, IL, USA Duration: 1994 Oct 2 → 1994 Oct 6 |
Conference
| Conference | Proceedings of the 1994 TMS Fall Symposium |
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| City | Rosemont, IL, USA |
| Period | 94/10/2 → 94/10/6 |