Abstract
Medium-entropy alloys strengthened by the L12-type coherent precipitates were recently proposed, whereas the mechanical property still needs to be improved. Here, we demonstrated a strategy for notably improving the strength of the representative (CoCrNi)94Ti3Al3 alloy, in which the refinement of grain structures and the promotion of precipitation were concurrently achieved by pre-strain followed by aging. A refined grain structure containing incoherent σ-precipitates and a large number of coherent L12-precipitates was formed, which enhances the yield strength and ultimate tensile strength up to 1431 MPa and 1683 MPa respectively. Furthermore, decreasing pre-strain temperature or increasing strain further aids the enhancement. The present study opens an avenue for fabricating high-performance precipitation-strengthened alloys.
Original language | English |
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Article number | 141390 |
Journal | Materials Science and Engineering A |
Volume | 819 |
DOIs | |
Publication status | Published - 2021 Jul 5 |
Keywords
- Annealing
- Mechanical property
- Medium-entropy alloy
- Pre-straining
- Precipitation
- Ultrafine structure
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering