Coarsening phenomenon of L1{sub 2} precipitates in rapidly solidified Al-3at%(Ti, V, Zr) system
- Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of). Dept. of Materials Science and Engineering
It is of interest how to design the Al-Ti-V-Zr system and optimize the compositions of added transition elements to minimize the lattice misfit, and thus an interfacial energy, and maximize the coarsening resistance and, at the same time, optimize the volume fraction of the precipitated stable D0{sub 23} Al{sub 3}M phase. These all can be beneficial to the high temperature strength. The coarsening kinetics of the L1{sub 2} precipitate in the present study were very slow. Furthermore, the transformation of the L1{sub 2} phase to the D0{sub 23} phase was not observed. The free energy change for the L1{sub 2}-D0{sub 23} transformation was probably reduced due to the reduction in lattice misfit and strain. In the previous works, the authors designed alloys assuming the stable DO{sub 23} phase would play an active role in the aging condition, but this prediction was not observed. Instead, L1{sub 2} precipitates were dominant. Owing to the low coarsening rate and these high thermal stability of the precipitated phases, Al-Ti-V-Zr systems show promise as bases for high-temperature high-strength Al alloys.
- OSTI ID:
- 105939
- Journal Information:
- Scripta Metallurgica et Materialia, Journal Name: Scripta Metallurgica et Materialia Journal Issue: 5 Vol. 33; ISSN 0956-716X; ISSN SCRMEX
- Country of Publication:
- United States
- Language:
- English
Similar Records
Thermal stability of L1 sub 2 structured Al sub 3 (Zr sub x V sub 1-x ) in rapidly solidified Al-Zr-V alloys
Design of high-temperature high-strength Al-Ti-V-Zr alloys