|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Advances in Multi-Principal Elements Alloys X
||Fabrication and Investigation of Lightweight Porous Titanium-containing Medium and High-entropy Alloys by Freeze Casting
||Kuan-Cheng Lai, Ko-Kai Tseng, Jien-Wei Yeh, Po-Yu Chen
|On-Site Speaker (Planned)
The freeze-casting technique can manufacture anisotropic, interconnected porous materials. In this study, porous TiNbCr medium-entropy alloy and Al0.5CoCrFeNi2Ti0.5 high-entropy alloy were developed by freeze-casting with gas-atomized powders. The particles were spherical in shape with an average diameter of ~10 μm. Our study focused on how processing parameters, such as cooling rate, sintering temperature, and solid loading, could affect microstructure and mechanical behaviors of the alloys. We sintered the porous alloys under hydrogen atmosphere to prevent oxidation. By applying 5℃/min freezing rate and 20 vol% solid loading, porous Ti-containing alloys were fabricated with aligned porous microstructure. The volume shrinkage, scaffold density, and porosity were in the range of 30-36%, 1.5-2 g/cm3 and 65-71%, respectively. Compressive mechanical properties were improved with increasing sintering temperature and duration. The freeze-casted alloys exhibited anisotropic mechanical performance compared to typical metal foams. Integrating freeze-casting with gas-atomization, porous alloys can be fabricated and applied in various fields.
||High-Entropy Alloys, Mechanical Properties, Process Technology