About this Abstract |
Meeting |
MS&T23: Materials Science & Technology
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Symposium
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High Entropy Materials: Concentrated Solid Solutions, Intermetallics, Ceramics, Functional Materials and Beyond IV
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Presentation Title |
F-7: Lightweight Refractory High Entropy Alloys with Excellent Specific Strength and Enhanced Ductility By In-situ Heterogeneous Structure |
Author(s) |
Lianxi Hu, Yu Sun, Yuan Yuan, Fei Gao |
On-Site Speaker (Planned) |
Lianxi Hu |
Abstract Scope |
A novel category of lightweight Tix(x=0.5-2)AlV0.5CrMo refractory high-entropy alloys (RHEAs) have been designed by tailoring the in-situ forming of heterogeneous structures during spark plasma sintering (SPS). The effect of Ti on the microstructure evolution and mechanical properties was thoroughly investigated. All the as-milled alloy powders were found to present a single body-centered cubic (BCC) phase structure. At high temperature above 1200 °C, however, the disordered BCC2 and hexagonal Al2O3 phases formed from the metastable BCC solid solution. The grain sizes of both the BCC and the newly-formed BCC2 and Al2O3 phases were in the range of 0.13-0.41 μm. Mechanical tests showed that the Tix(x=0.5-2)AlV0.5CrMo RHEAs possessed ultra-high specific strength, due to the grain size refinement strengthening and hetero-deformation induced (HDI) hardening. In particular, the Ti1.5AlV0.5CrMo RHEA presented an excellent specific compressive yield strength as high as 385.3 MPa.cm3/g combined with an enhanced fracture strain of 18.0%. |